feat(FN-5328): guard malformed mission hierarchy data in MissionManager

- test(FN-5328): assert mission detail load error logging path
- test(FN-5328): mock lucide icons in mission recovery regression
- test(FN-5328): add malformed mission detail recovery regression
- fix(FN-5328): guard malformed mission hierarchy payloads

Fusion-Task-Id: FN-5328

packages/dashboard/app/components/MissionManager.tsx

@@ -472,6 +472,35 @@ function getAutopilotActivitySummary(state: AutopilotState, lastActivityAt?: str
   return `Last activation ${getRelativeTime(lastActivityAt)}`;
 }
 
+function normalizeMissionHierarchy(mission: MissionWithHierarchy): MissionWithHierarchy {
+  if (!Array.isArray(mission.milestones)) {
+    throw new Error("Malformed mission detail response: missing milestones");
+  }
+
+  return {
+    ...mission,
+    milestones: mission.milestones.map((milestone) => {
+      if (!Array.isArray(milestone.slices)) {
+        throw new Error(`Malformed mission detail response: milestone ${milestone.id} is missing slices`);
+      }
+
+      return {
+        ...milestone,
+        slices: milestone.slices.map((slice) => {
+          if (!Array.isArray(slice.features)) {
+            throw new Error(`Malformed mission detail response: slice ${slice.id} is missing features`);
+          }
+
+          return {
+            ...slice,
+            features: slice.features,
+          };
+        }),
+      };
+    }),
+  };
+}
+
 export function MissionManager({ isOpen, isInline = false, onClose, addToast, projectId, onSelectTask, availableTasks = [], resumeSessionId, targetMissionId, milestoneSliceResumeSessionId, onMilestoneSliceResumeFetchError }: MissionManagerProps) {
   const isActive = isInline || isOpen;
   const cacheSuffix = projectId ?? "";
@@ -837,13 +866,12 @@ export function MissionManager({ isOpen, isInline = false, onClose, addToast, pr
   const loadMissionDetail = useCallback(async (missionId: string) => {
     try {
       setDetailLoading(true);
-      const data = await fetchMission(missionId, projectId);
-      // Guard against malformed responses (e.g. test fetch fallbacks): without
-      // a milestones array the detail view crashes on `.milestones.length`.
-      if (!data || !Array.isArray((data as MissionWithHierarchy).milestones)) {
-        setDetailLoading(false);
-        return;
+      const payload = await fetchMission(missionId, projectId);
+      if (!payload || typeof payload !== "object") {
+        throw new Error("Malformed mission detail response");
       }
+
+      const data = normalizeMissionHierarchy(payload as MissionWithHierarchy);
       setSelectedMission(data);
       if (data.milestones.length > 0) {
         const firstMilestoneId = data.milestones[0].id;
@@ -901,6 +929,7 @@ export function MissionManager({ isOpen, isInline = false, onClose, addToast, pr
         setValidationTelemetry(null);
       }
     } catch (err) {
+      console.error("[MissionManager] loadMissionDetail:", err);
       addToast(getErrorMessage(err) || "Failed to load mission details", "error");
     } finally {
       setDetailLoading(false);

packages/dashboard/app/components/__tests__/MissionManager.error-recovery.test.tsx

@@ -0,0 +1,115 @@
+import { describe, it, expect, vi, beforeEach } from "vitest";
+import { render, screen, fireEvent, waitFor } from "@testing-library/react";
+import { PageErrorBoundary } from "../ErrorBoundary";
+import { MissionManager } from "../MissionManager";
+
+const mockFetchMissions = vi.fn();
+const mockFetchMission = vi.fn();
+const mockFetchMissionsHealth = vi.fn();
+const mockFetchAiSessions = vi.fn();
+const mockFetchMissionInterviewDrafts = vi.fn();
+
+vi.mock("../../hooks/useNavigationHistory", async (importOriginal) => {
+  const actual = await importOriginal<typeof import("../../hooks/useNavigationHistory")>();
+  return {
+    ...actual,
+    useNavigationHistoryContext: () => ({ pushNav: vi.fn(), replaceCurrent: vi.fn() }),
+  };
+});
+
+vi.mock("../../api", async (importOriginal) => {
+  const actual = await importOriginal<typeof import("../../api")>();
+  return {
+    ...actual,
+    fetchMissions: (...args: unknown[]) => mockFetchMissions(...args),
+    fetchMission: (...args: unknown[]) => mockFetchMission(...args),
+    fetchMissionsHealth: (...args: unknown[]) => mockFetchMissionsHealth(...args),
+    fetchAiSessions: (...args: unknown[]) => mockFetchAiSessions(...args),
+    fetchMissionInterviewDrafts: (...args: unknown[]) => mockFetchMissionInterviewDrafts(...args),
+  };
+});
+
+vi.mock("lucide-react", () => ({
+  X: () => <span>X</span>,
+  Plus: () => <span>+</span>,
+  Pencil: () => <span>Pencil</span>,
+  Trash2: () => <span>Trash</span>,
+  ChevronRight: () => <span>ChevronRight</span>,
+  ChevronDown: () => <span>ChevronDown</span>,
+  ChevronLeft: () => <span>ChevronLeft</span>,
+  Target: () => <span>Target</span>,
+  Layers: () => <span>Layers</span>,
+  Package: () => <span>Package</span>,
+  Box: () => <span>Box</span>,
+  Check: () => <span>Check</span>,
+  Loader2: () => <span>Loader</span>,
+  Link: () => <span>Link</span>,
+  Unlink: () => <span>Unlink</span>,
+  Play: () => <span>Play</span>,
+  Square: () => <span>Square</span>,
+  Sparkles: () => <span>Sparkles</span>,
+  Zap: () => <span>Zap</span>,
+  Activity: () => <span>Activity</span>,
+  FileText: () => <span>FileText</span>,
+  RefreshCw: () => <span>Refresh</span>,
+}));
+
+describe("MissionManager malformed mission recovery", () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+    localStorage.clear();
+    mockFetchMissions.mockResolvedValue([
+      { id: "M-001", title: "Malformed Mission", description: "", status: "planning", milestones: [] },
+    ]);
+    mockFetchMissionsHealth.mockResolvedValue({});
+    mockFetchAiSessions.mockResolvedValue([]);
+    mockFetchMissionInterviewDrafts.mockResolvedValue([]);
+    mockFetchMission.mockResolvedValue({
+      id: "M-001",
+      title: "Malformed Mission",
+      description: "",
+      status: "planning",
+      milestones: [
+        {
+          id: "MS-001",
+          title: "Milestone missing slices",
+          description: "",
+          acceptanceCriteria: "",
+          status: "planning",
+          missionId: "M-001",
+          // intentionally malformed
+          slices: undefined,
+        },
+      ],
+    });
+  });
+
+  it("avoids page ErrorBoundary fallback and shows toast on malformed mission detail", async () => {
+    const addToast = vi.fn();
+    const consoleErrorSpy = vi.spyOn(console, "error").mockImplementation(() => {});
+
+    render(
+      <PageErrorBoundary>
+        <MissionManager isInline isOpen onClose={() => {}} addToast={addToast} />
+      </PageErrorBoundary>,
+    );
+
+    await screen.findByText("Malformed Mission");
+    fireEvent.click(screen.getByText("Malformed Mission"));
+
+    await waitFor(() => {
+      expect(screen.queryByText("Something went wrong")).not.toBeInTheDocument();
+    });
+
+    await waitFor(() => {
+      expect(addToast).toHaveBeenCalledWith(expect.stringMatching(/failed to load mission details|malformed/i), "error");
+    });
+
+    expect(consoleErrorSpy).toHaveBeenCalledWith(
+      "[MissionManager] loadMissionDetail:",
+      expect.any(Error),
+    );
+    expect(screen.getByTestId("mission-header-title")).toHaveTextContent("Missions");
+    expect(screen.getByText("Malformed Mission")).toBeInTheDocument();
+  });
+});