FN-7305: add prompt file access to task plans

Expose task plans as the user-facing Definition tab label and add a direct PROMPT.md editor entry point.

- Rename the task detail Definition tab label to Plan while preserving the existing tab id.
- Add an Open PROMPT.md action that uses the file browser provider for project task plan files.
- Adjust Plan action row layout for multiple buttons and mobile wrapping.
- Cover the Plan label and PROMPT.md action with task detail modal tests.
- Add a published package changeset for the dashboard task plan improvement.

Files changed:
 .changeset/tidy-plan-prompt-editor.md              |  7 +++
 .../dashboard/app/components/TaskDetailModal.css   | 14 ++++++
 .../dashboard/app/components/TaskDetailModal.tsx   | 20 +++++++-
 .../TaskDetailModal.definition-actions.test.tsx    | 55 +++++++++++++++++-----
 4 files changed, 83 insertions(+), 13 deletions(-)

Fusion-Task-Id: FN-7305

Fusion-Task-Lineage: afe732f9-e9a1-409f-9b09-ae1deccbe3be

Co-authored-by: Fusion (runfusion.ai) <noreply@runfusion.ai>

.changeset/tidy-plan-prompt-editor.md

@@ -0,0 +1,7 @@
+---
+"@runfusion/fusion": minor
+---
+
+summary: Rename the task Definition tab to Plan and add a PROMPT.md editor action.
+category: feature
+dev: Dashboard task details now open the current task's PROMPT.md via FileBrowserProvider.

packages/dashboard/app/components/TaskDetailModal.css

@@ -851,9 +851,23 @@ Expanded chat must also cover the task metadata row — priority, execution mode
 
 
 .detail-spec-edit-trigger {
+  display: flex;
+  flex-wrap: wrap;
+  align-items: center;
+  gap: var(--space-sm);
   margin-bottom: var(--space-md);
 }
 
+@media (max-width: 768px) {
+  .detail-spec-edit-trigger {
+    align-items: stretch;
+  }
+
+  .detail-spec-edit-trigger .btn {
+    flex: 1 1 auto;
+  }
+}
+
 .detail-attachments-grid {
   display: flex;
   flex-wrap: wrap;

packages/dashboard/app/components/TaskDetailModal.tsx

@@ -66,6 +66,7 @@ import { getTaskLogEntryAction, getTaskLogEntryOutcome } from "../utils/taskLogE
 import { getRelativeTimeBucket } from "../utils/relativeTimeAgo";
 import { ACTIVE_STATUSES, resolveEffectiveExecutor, resolveEffectivePlanning, resolveEffectiveValidator, type ModelSelection } from "./effective-model-resolution";
 import { TaskContextMenu, buildTaskActionMenuModel, getTaskPrAutomationLabel } from "./TaskContextMenu";
+import { useFileBrowser } from "../context/FileBrowserContext";
 
 const STALE_PAUSED_REVIEW_LOG_REGEX = /^Stale paused review surfaced \[([^\]]+)\]/;
 const EMPTY_MARKDOWN_CHILD_SEPARATOR = "";
@@ -513,6 +514,7 @@ export function TaskDetailContent({
 }: TaskDetailContentProps) {
   const { t } = useTranslation("app");
   const columnLabel = useColumnLabel();
+  const fileBrowser = useFileBrowser();
   const [activeTab, setActiveTab] = useState<TabId>(() => resolveDefaultTab(initialTab, task.column));
   const [chatExpanded, setChatExpanded] = useState(false);
 
@@ -607,6 +609,9 @@ export function TaskDetailContent({
     () => getUnifiedTaskProgress(workingTask),
     [workingTask.steps, workingTask.enabledWorkflowSteps, workingTask.workflowStepResults],
   );
+  const openPromptFile = useCallback(() => {
+    fileBrowser?.openFile(`.fusion/tasks/${workingTask.id}/PROMPT.md`, { workspace: "project" });
+  }, [fileBrowser, workingTask.id]);
   const canRetryTask =
     task.status === "failed" ||
     task.status === "stuck-killed" ||
@@ -3155,7 +3160,7 @@ export function TaskDetailContent({
               className={`detail-tab${activeTab === "definition" ? " detail-tab-active" : ""}`}
               onClick={() => setActiveTab("definition")}
             >
-              {t("taskDetail.tabs.definition", "Definition")}
+              {t("taskDetail.tabs.definition", "Plan")}
             </button>
             <button
               className={`detail-tab${activeTab === "logs" ? " detail-tab-active" : ""}`}
@@ -3775,6 +3780,19 @@ export function TaskDetailContent({
           <div className="detail-section">
             {!isEditingSpec && (
               <div className="detail-spec-edit-trigger">
+                {/*
+                FNXC:TaskDetailPlan 2026-06-30-00:00:
+                The Plan tab keeps the internal definition route for stable links, while exposing a direct PROMPT.md editor action so operators can comment on the executable task plan file without replacing the inline AI revision flow.
+                */}
+                {fileBrowser && (
+                  <button
+                    className="btn btn-sm"
+                    onClick={openPromptFile}
+                    title={t("taskDetail.spec.openPromptTitle", "Open this task's PROMPT.md in the file editor")}
+                  >
+                    {t("taskDetail.spec.openPromptBtn", "Open PROMPT.md")}
+                  </button>
+                )}
                 <button className="btn btn-sm" onClick={enterSpecEditMode}>
                   {t("taskDetail.spec.editBtn", "Edit")}
                 </button>

packages/dashboard/app/components/__tests__/TaskDetailModal.definition-actions.test.tsx

@@ -15,13 +15,14 @@ import {
   setupTaskDetailModalHooks,
 } from "./TaskDetailModal.test-helpers";
 import { TaskDetailModal, TaskDetailContent } from "../TaskDetailModal";
+import { FileBrowserProvider } from "../../context/FileBrowserContext";
 import { readBoardWorkflowSelection, removeBoardWorkflowSelection, writeBoardWorkflowSelection } from "../../utils/boardWorkflowSelection";
 
 setupTaskDetailModalHooks();
 
 describe("TaskDetailModal", () => {
-  describe("Definition tab edit mode", () => {
+  describe("Plan tab edit mode", () => {
-    it("shows Edit button in Definition tab", () => {
+    it("shows Edit button in Plan tab", () => {
       render(
         <TaskDetailModal
           task={makeTask({ prompt: "# Test\n\nSpec content." })}
@@ -35,9 +36,39 @@ describe("TaskDetailModal", () => {
         />,
       );
 
+      expect(screen.getByRole("button", { name: "Plan" })).toBeTruthy();
+      expect(screen.queryByRole("button", { name: "Definition" })).toBeNull();
       expect(screen.getByText("Edit")).toBeTruthy();
     });
 
+    it("opens the task PROMPT.md file from the near-top Plan action", async () => {
+      const user = userEvent.setup();
+      const openFile = vi.fn();
+      const { container } = render(
+        <FileBrowserProvider openFile={openFile}>
+          <TaskDetailModal
+            task={makeTask({ id: "FN-099", prompt: "# Test\n\nSpec content." })}
+            initialTab="definition"
+            onClose={noop}
+            onMoveTask={noopMove}
+            onDeleteTask={noopDelete}
+            onMergeTask={noopMerge}
+            onOpenDetail={noopOpenDetail}
+            addToast={noop}
+          />
+        </FileBrowserProvider>,
+      );
+
+      const actionRow = container.querySelector(".detail-spec-edit-trigger");
+      expect(actionRow).toBeTruthy();
+      const promptButton = screen.getByRole("button", { name: "Open PROMPT.md" });
+      expect(actionRow?.contains(promptButton)).toBe(true);
+
+      await user.click(promptButton);
+
+      expect(openFile).toHaveBeenCalledWith(".fusion/tasks/FN-099/PROMPT.md", { workspace: "project" });
+    });
+
     it("clicking Edit shows textarea with current prompt content", () => {
       const { container } = render(
         <TaskDetailModal
@@ -191,11 +222,11 @@ describe("TaskDetailModal", () => {
       );
 
       // In-progress tasks show exactly 11 tabs:
-      // Chat, Definition, Logs, Changes, Review, Comments, Artifacts, Model, Workflow, Stats, Routing
+      // Chat, Plan, Logs, Changes, Review, Comments, Artifacts, Model, Workflow, Stats, Routing
       const tabs = container.querySelectorAll(".detail-tab");
       expect(tabs.length).toBe(11);
       expect(tabs[0].textContent).toBe("Chat");
-      expect(tabs[1].textContent).toBe("Definition");
+      expect(tabs[1].textContent).toBe("Plan");
       expect(tabs[2].textContent).toBe("Logs");
       expect(tabs[3].textContent).toBe("Changes");
       expect(tabs[4].textContent).toBe("Review");
@@ -227,7 +258,7 @@ describe("TaskDetailModal", () => {
       const tabs = container.querySelectorAll(".detail-tab");
       expect(tabs.length).toBe(11);
       expect(tabs[0].textContent).toBe("Chat");
-      expect(tabs[1].textContent).toBe("Definition");
+      expect(tabs[1].textContent).toBe("Plan");
       expect(tabs[2].textContent).toBe("Logs");
       expect(tabs[3].textContent).toBe("Changes");
       expect(tabs[4].textContent).toBe("Review");
@@ -256,12 +287,12 @@ describe("TaskDetailModal", () => {
         />,
       );
 
-      // Done task with commit SHA: Summary, Chat, Definition, Logs, Changes, Review, Comments, Artifacts, Model, Workflow, Stats, Routing (12 tabs, no Commits)
+      // Done task with commit SHA: Summary, Chat, Plan, Logs, Changes, Review, Comments, Artifacts, Model, Workflow, Stats, Routing (12 tabs, no Commits)
       const tabs = container.querySelectorAll(".detail-tab");
       expect(tabs.length).toBe(12);
       expect(tabs[0].textContent).toBe("Summary");
       expect(tabs[1].textContent).toBe("Chat");
-      expect(tabs[2].textContent).toBe("Definition");
+      expect(tabs[2].textContent).toBe("Plan");
       expect(tabs[3].textContent).toBe("Logs");
       expect(tabs[4].textContent).toBe("Changes");
       expect(tabs[5].textContent).toBe("Review");
@@ -298,7 +329,7 @@ describe("TaskDetailModal", () => {
       expect(tabs.length).toBe(12);
       expect(tabs[0].textContent).toBe("Summary");
       expect(tabs[1].textContent).toBe("Chat");
-      expect(tabs[2].textContent).toBe("Definition");
+      expect(tabs[2].textContent).toBe("Plan");
       expect(tabs[3].textContent).toBe("Logs");
       expect(tabs[4].textContent).toBe("Changes");
       expect(tabs[5].textContent).toBe("Review");
@@ -327,9 +358,9 @@ describe("TaskDetailModal", () => {
       );
 
       const triageTabs = triageContainer.querySelectorAll(".detail-tab");
-      expect(triageTabs.length).toBe(10); // Chat, Definition, Logs, Review, Comments, Artifacts, Model, Workflow, Stats, Routing
+      expect(triageTabs.length).toBe(10); // Chat, Plan, Logs, Review, Comments, Artifacts, Model, Workflow, Stats, Routing
       expect(Array.from(triageTabs).map(t => t.textContent)).toEqual([
-        "Chat", "Definition", "Logs", "Review", "Comments", "Artifacts", "Model", "Workflow", "Stats", "Routing",
+        "Chat", "Plan", "Logs", "Review", "Comments", "Artifacts", "Model", "Workflow", "Stats", "Routing",
       ]);
 
       const { container: todoContainer } = render(
@@ -346,9 +377,9 @@ describe("TaskDetailModal", () => {
       );
 
       const todoTabs = todoContainer.querySelectorAll(".detail-tab");
-      expect(todoTabs.length).toBe(10); // Chat, Definition, Logs, Review, Comments, Artifacts, Model, Workflow, Stats, Routing
+      expect(todoTabs.length).toBe(10); // Chat, Plan, Logs, Review, Comments, Artifacts, Model, Workflow, Stats, Routing
       expect(Array.from(todoTabs).map(t => t.textContent)).toEqual([
-        "Chat", "Definition", "Logs", "Review", "Comments", "Artifacts", "Model", "Workflow", "Stats", "Routing",
+        "Chat", "Plan", "Logs", "Review", "Comments", "Artifacts", "Model", "Workflow", "Stats", "Routing",
       ]);
     });