feat(FN-847): add conditional Workflow tab to TaskDetailModal

- Show Workflow tab for tasks with enabled workflow steps OR previous workflow results
- Add comprehensive tests for TaskDetailModal workflow tab visibility
- Add workflow tab styles including step result cards and status badges
- Clean up TerminalModal and useTerminalSessions (remove unused code and tests)
- Remove dashboard README section on terminal sessions

packages/dashboard/app/components/TaskDetailModal.tsx

@@ -4,7 +4,8 @@ import ReactMarkdown from "react-markdown";
 import remarkGfm from "remark-gfm";
 import type { Task, TaskDetail, TaskAttachment, Column, MergeResult, PrInfo, Settings } from "@fusion/core";
 import { COLUMN_LABELS, VALID_TRANSITIONS } from "@fusion/core";
-import { uploadAttachment, deleteAttachment, updateTask, pauseTask, unpauseTask, fetchTaskDetail, fetchSettings, requestSpecRevision, approvePlan, rejectPlan, refineTask } from "../api";
+import { uploadAttachment, deleteAttachment, updateTask, pauseTask, unpauseTask, fetchTaskDetail, fetchSettings, requestSpecRevision, approvePlan, rejectPlan, refineTask, fetchWorkflowResults } from "../api";
+import type { WorkflowStepResult } from "@fusion/core";
 import type { ToastType } from "../hooks/useToast";
 import { useAgentLogs } from "../hooks/useAgentLogs";
 import { AgentLogViewer } from "./AgentLogViewer";
@@ -15,6 +16,7 @@ import { MergeDetails } from "./MergeDetails";
 import { TaskChangesTab } from "./TaskChangesTab";
 import { CommitDiffTab } from "./CommitDiffTab";
 import { TaskForm, type PendingImage } from "./TaskForm";
+import { WorkflowResultsTab } from "./WorkflowResultsTab";
 
 interface ModelSelection {
   provider?: string;
@@ -151,7 +153,7 @@ export function TaskDetailModal({
   addToast,
   githubTokenConfigured,
 }: TaskDetailModalProps) {
-  const [activeTab, setActiveTab] = useState<"definition" | "logs" | "changes" | "commits" | "comments" | "model">("definition");
+  const [activeTab, setActiveTab] = useState<"definition" | "logs" | "changes" | "commits" | "comments" | "model" | "workflow">("definition");
   const [logSubview, setLogSubview] = useState<"activity" | "agent-log">("activity");
   const [attachments, setAttachments] = useState<TaskAttachment[]>(task.attachments || []);
   const [uploading, setUploading] = useState(false);
@@ -183,6 +185,10 @@ export function TaskDetailModal({
   // Merged project settings for effective model resolution in Agent Log header
   const [settings, setSettings] = useState<Settings | undefined>(undefined);
 
+  // Workflow results state
+  const [workflowResults, setWorkflowResults] = useState<WorkflowStepResult[]>([]);
+  const [workflowResultsLoading, setWorkflowResultsLoading] = useState(false);
+
   // Reset edit state when task changes
   useEffect(() => {
     setEditTitle(task.title || "");
@@ -203,6 +209,27 @@ export function TaskDetailModal({
     return () => { cancelled = true; };
   }, [projectId]);
 
+  // Load workflow results when workflow tab is active
+  const hasWorkflowSteps = (task.enabledWorkflowSteps?.length ?? 0) > 0 || (task.workflowStepResults?.length ?? 0) > 0;
+  useEffect(() => {
+    if (activeTab !== "workflow" || !hasWorkflowSteps) return;
+    let cancelled = false;
+    setWorkflowResultsLoading(true);
+    fetchWorkflowResults(task.id, projectId)
+      .then((results) => {
+        if (!cancelled) setWorkflowResults(results);
+      })
+      .catch((err: any) => {
+        if (!cancelled) {
+          addToast(`Failed to load workflow results: ${err.message}`, "error");
+        }
+      })
+      .finally(() => {
+        if (!cancelled) setWorkflowResultsLoading(false);
+      });
+    return () => { cancelled = true; };
+  }, [activeTab, task.id, projectId, hasWorkflowSteps, addToast]);
+
   // Reset dependency search when dropdown closes
   useEffect(() => {
     if (!showDepDropdown) {
@@ -771,8 +798,20 @@ export function TaskDetailModal({
             >
               Model
             </button>
+            {hasWorkflowSteps && (
+              <button
+                className={`detail-tab${activeTab === "workflow" ? " detail-tab-active" : ""}`}
+                onClick={() => setActiveTab("workflow")}
+              >
+                Workflow
+              </button>
+            )}
           </div>
-          {activeTab === "model" ? (
+          {activeTab === "workflow" ? (
+            <div className="detail-section">
+              <WorkflowResultsTab taskId={task.id} results={workflowResults} loading={workflowResultsLoading} />
+            </div>
+          ) : activeTab === "model" ? (
             <div className="detail-section">
               <ModelSelectorTab task={task} addToast={addToast} />
             </div>

packages/dashboard/app/components/__tests__/TaskDetailModal.test.tsx

@@ -24,6 +24,7 @@ vi.mock("../../api", () => ({
   updateGlobalSettings: vi.fn().mockResolvedValue({}),
   pauseTask: vi.fn().mockResolvedValue({}),
   unpauseTask: vi.fn().mockResolvedValue({}),
+  fetchWorkflowResults: vi.fn().mockResolvedValue([]),
 }));
 
 // Mock lucide-react icons used by TaskDetailModal, TaskForm, PrSection, CustomModelDropdown
@@ -3557,4 +3558,263 @@ describe("TaskDetailModal", () => {
       });
     });
   });
+
+  describe("Workflow tab", () => {
+    it("does NOT show Workflow tab when enabledWorkflowSteps is empty", () => {
+      const { container } = render(
+        <TaskDetailModal
+          task={makeTask({ enabledWorkflowSteps: [] })}
+          onClose={noop}
+          onMoveTask={noopMove}
+          onDeleteTask={noopDelete}
+          onMergeTask={noopMerge}
+          onOpenDetail={noopOpenDetail}
+          addToast={noop}
+        />,
+      );
+
+      expect(screen.queryByText("Workflow")).toBeNull();
+    });
+
+    it("does NOT show Workflow tab when enabledWorkflowSteps is undefined", () => {
+      const { container } = render(
+        <TaskDetailModal
+          task={makeTask({ enabledWorkflowSteps: undefined, workflowStepResults: undefined })}
+          onClose={noop}
+          onMoveTask={noopMove}
+          onDeleteTask={noopDelete}
+          onMergeTask={noopMerge}
+          onOpenDetail={noopOpenDetail}
+          addToast={noop}
+        />,
+      );
+
+      expect(screen.queryByText("Workflow")).toBeNull();
+    });
+
+    it("shows Workflow tab when enabledWorkflowSteps is non-empty", () => {
+      render(
+        <TaskDetailModal
+          task={makeTask({ enabledWorkflowSteps: ["WS-001"] })}
+          onClose={noop}
+          onMoveTask={noopMove}
+          onDeleteTask={noopDelete}
+          onMergeTask={noopMerge}
+          onOpenDetail={noopOpenDetail}
+          addToast={noop}
+        />,
+      );
+
+      expect(screen.getByText("Workflow")).toBeTruthy();
+    });
+
+    it("shows Workflow tab when task has previous workflow results", () => {
+      render(
+        <TaskDetailModal
+          task={makeTask({
+            enabledWorkflowSteps: [],
+            workflowStepResults: [
+              { workflowStepId: "WS-001", workflowStepName: "QA Check", status: "passed" },
+            ],
+          })}
+          onClose={noop}
+          onMoveTask={noopMove}
+          onDeleteTask={noopDelete}
+          onMergeTask={noopMerge}
+          onOpenDetail={noopOpenDetail}
+          addToast={noop}
+        />,
+      );
+
+      expect(screen.getByText("Workflow")).toBeTruthy();
+    });
+
+    it("switches to Workflow tab and calls fetchWorkflowResults", async () => {
+      const { fetchWorkflowResults } = await import("../../api");
+      const mockFetch = vi.mocked(fetchWorkflowResults);
+      const mockResults: import("@fusion/core").WorkflowStepResult[] = [
+        {
+          workflowStepId: "WS-001",
+          workflowStepName: "QA Check",
+          status: "passed",
+          output: "All tests passed.",
+          startedAt: "2026-04-04T10:00:00Z",
+          completedAt: "2026-04-04T10:02:00Z",
+        },
+      ];
+      mockFetch.mockResolvedValueOnce(mockResults);
+
+      render(
+        <TaskDetailModal
+          task={makeTask({ enabledWorkflowSteps: ["WS-001"] })}
+          onClose={noop}
+          onMoveTask={noopMove}
+          onDeleteTask={noopDelete}
+          onMergeTask={noopMerge}
+          onOpenDetail={noopOpenDetail}
+          addToast={noop}
+        />,
+      );
+
+      fireEvent.click(screen.getByText("Workflow"));
+
+      await waitFor(() => {
+        expect(mockFetch).toHaveBeenCalledWith("FN-099", undefined);
+      });
+
+      // Should render the workflow results
+      expect(screen.getByText("QA Check")).toBeTruthy();
+    });
+
+    it("shows loading state when workflow results are being fetched", async () => {
+      const { fetchWorkflowResults } = await import("../../api");
+      const mockFetch = vi.mocked(fetchWorkflowResults);
+      // Never resolve to keep loading state
+      mockFetch.mockReturnValueOnce(new Promise(() => {}));
+
+      render(
+        <TaskDetailModal
+          task={makeTask({ enabledWorkflowSteps: ["WS-001"] })}
+          onClose={noop}
+          onMoveTask={noopMove}
+          onDeleteTask={noopDelete}
+          onMergeTask={noopMerge}
+          onOpenDetail={noopOpenDetail}
+          addToast={noop}
+        />,
+      );
+
+      fireEvent.click(screen.getByText("Workflow"));
+
+      await waitFor(() => {
+        expect(screen.getByTestId("workflow-results-loading")).toBeTruthy();
+      });
+    });
+
+    it("shows error toast when fetchWorkflowResults fails", async () => {
+      const { fetchWorkflowResults } = await import("../../api");
+      const mockFetch = vi.mocked(fetchWorkflowResults);
+      mockFetch.mockRejectedValueOnce(new Error("Server error"));
+      const addToast = vi.fn();
+
+      render(
+        <TaskDetailModal
+          task={makeTask({ enabledWorkflowSteps: ["WS-001"] })}
+          onClose={noop}
+          onMoveTask={noopMove}
+          onDeleteTask={noopDelete}
+          onMergeTask={noopMerge}
+          onOpenDetail={noopOpenDetail}
+          addToast={addToast}
+        />,
+      );
+
+      fireEvent.click(screen.getByText("Workflow"));
+
+      await waitFor(() => {
+        expect(addToast).toHaveBeenCalledWith(
+          "Failed to load workflow results: Server error",
+          "error",
+        );
+      });
+    });
+
+    it("renders empty state when workflow results are empty", async () => {
+      const { fetchWorkflowResults } = await import("../../api");
+      const mockFetch = vi.mocked(fetchWorkflowResults);
+      mockFetch.mockResolvedValueOnce([]);
+
+      render(
+        <TaskDetailModal
+          task={makeTask({ enabledWorkflowSteps: ["WS-001"] })}
+          onClose={noop}
+          onMoveTask={noopMove}
+          onDeleteTask={noopDelete}
+          onMergeTask={noopMerge}
+          onOpenDetail={noopOpenDetail}
+          addToast={noop}
+        />,
+      );
+
+      fireEvent.click(screen.getByText("Workflow"));
+
+      await waitFor(() => {
+        expect(screen.getByTestId("workflow-results-empty")).toBeTruthy();
+        expect(screen.getByText("No workflow steps have run yet.")).toBeTruthy();
+      });
+    });
+
+    it("renders multiple workflow step results with status badges", async () => {
+      const { fetchWorkflowResults } = await import("../../api");
+      const mockFetch = vi.mocked(fetchWorkflowResults);
+      const mockResults: import("@fusion/core").WorkflowStepResult[] = [
+        {
+          workflowStepId: "WS-001",
+          workflowStepName: "QA Check",
+          status: "passed",
+          output: "All tests passed.",
+          startedAt: "2026-04-04T10:00:00Z",
+          completedAt: "2026-04-04T10:02:00Z",
+        },
+        {
+          workflowStepId: "WS-002",
+          workflowStepName: "Security Audit",
+          status: "failed",
+          output: "Found 2 issues.",
+          startedAt: "2026-04-04T10:02:05Z",
+          completedAt: "2026-04-04T10:03:00Z",
+        },
+      ];
+      mockFetch.mockResolvedValueOnce(mockResults);
+
+      render(
+        <TaskDetailModal
+          task={makeTask({ enabledWorkflowSteps: ["WS-001", "WS-002"] })}
+          onClose={noop}
+          onMoveTask={noopMove}
+          onDeleteTask={noopDelete}
+          onMergeTask={noopMerge}
+          onOpenDetail={noopOpenDetail}
+          addToast={noop}
+        />,
+      );
+
+      fireEvent.click(screen.getByText("Workflow"));
+
+      await waitFor(() => {
+        expect(screen.getByText("QA Check")).toBeTruthy();
+        expect(screen.getByText("Security Audit")).toBeTruthy();
+        expect(screen.getByTestId("workflow-result-badge-WS-001")).toHaveTextContent("Passed");
+        expect(screen.getByTestId("workflow-result-badge-WS-002")).toHaveTextContent("Failed");
+      });
+    });
+
+    it("hides Definition content when Workflow tab is active", async () => {
+      const { container } = render(
+        <TaskDetailModal
+          task={makeTask({
+            enabledWorkflowSteps: ["WS-001"],
+            prompt: "# Test prompt",
+          })}
+          onClose={noop}
+          onMoveTask={noopMove}
+          onDeleteTask={noopDelete}
+          onMergeTask={noopMerge}
+          onOpenDetail={noopOpenDetail}
+          addToast={noop}
+        />,
+      );
+
+      // Definition content visible initially
+      expect(container.querySelector(".markdown-body")).toBeTruthy();
+
+      // Switch to Workflow tab
+      fireEvent.click(screen.getByText("Workflow"));
+
+      // Definition content should be hidden
+      await waitFor(() => {
+        expect(container.querySelector(".markdown-body")).toBeNull();
+      });
+    });
+  });
 });

packages/dashboard/app/styles.css

@@ -16740,6 +16740,113 @@ html .column.drag-over * {
   }
 }
 
+/* ── Workflow Results ── */
+.workflow-results-loading {
+  display: flex;
+  align-items: center;
+  gap: var(--space-sm, 8px);
+  padding: var(--space-md, 16px);
+  color: var(--text-muted, #8b949e);
+  font-size: 14px;
+}
+
+.workflow-results-spinner {
+  width: 16px;
+  height: 16px;
+  border: 2px solid var(--border, #30363d);
+  border-top-color: var(--todo, #58a6ff);
+  border-radius: 50%;
+  animation: spin 0.6s linear infinite;
+}
+
+@keyframes spin {
+  to { transform: rotate(360deg); }
+}
+
+.workflow-results-empty {
+  padding: var(--space-md, 16px);
+  text-align: center;
+  color: var(--text-muted, #8b949e);
+}
+
+.workflow-results-empty-hint {
+  font-size: 12px;
+  margin-top: var(--space-xs, 4px);
+  opacity: 0.7;
+}
+
+.workflow-results-list {
+  display: flex;
+  flex-direction: column;
+  gap: var(--space-md, 16px);
+}
+
+.workflow-result-item {
+  border: 1px solid var(--border, #30363d);
+  border-radius: 8px;
+  padding: var(--space-md, 16px);
+  background: var(--surface-elevated, #161b22);
+}
+
+.workflow-result-header {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  gap: var(--space-sm, 8px);
+  margin-bottom: var(--space-xs, 4px);
+}
+
+.workflow-result-name {
+  font-weight: 600;
+  font-size: 14px;
+  color: var(--text-primary, #e6edf3);
+}
+
+.workflow-result-badge {
+  display: inline-block;
+  padding: 2px 8px;
+  border-radius: 12px;
+  font-size: 11px;
+  font-weight: 600;
+  text-transform: uppercase;
+  letter-spacing: 0.5px;
+}
+
+.workflow-result-meta {
+  display: flex;
+  gap: var(--space-sm, 8px);
+  font-size: 12px;
+  color: var(--text-muted, #8b949e);
+  margin-bottom: var(--space-xs, 4px);
+}
+
+.workflow-result-output-section {
+  margin-top: var(--space-sm, 8px);
+}
+
+.workflow-result-output-label {
+  font-size: 12px;
+  font-weight: 600;
+  color: var(--text-muted, #8b949e);
+  margin-bottom: var(--space-xs, 4px);
+}
+
+.workflow-result-output {
+  background: var(--surface-dimmed, #0d1117);
+  border: 1px solid var(--border, #30363d);
+  border-radius: 6px;
+  padding: var(--space-sm, 8px) var(--space-md, 16px);
+  font-family: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;
+  font-size: 12px;
+  line-height: 1.5;
+  color: var(--text-primary, #e6edf3);
+  white-space: pre-wrap;
+  word-break: break-word;
+  overflow-x: auto;
+  max-height: 300px;
+  overflow-y: auto;
+}
+
 /* ── Light Theme ── */
 [data-theme="light"] .mission-manager {
   background: var(--surface);