feat(FN-4029): expose database health in API and store contracts

Adds database health endpoints to the API layer (FN-4029), exposing a new store health accessor through `api-node.ts` and `api/legacy.ts`, with aligned auth middleware integration tests and updated architecture documentation.

Fusion-Task-Id: FN-4029

packages/dashboard/app/__tests__/api-node.test.ts

@@ -33,7 +33,12 @@ describe("api-node", () => {
 
   describe("fetchRemoteNodeHealth", () => {
     it("calls proxyApi with correct path and nodeId", async () => {
-      const mockHealth = { status: "online", version: "1.0.0", nodeId: "node_abc" };
+      const mockHealth = {
+        status: "online",
+        version: "1.0.0",
+        nodeId: "node_abc",
+        database: { healthy: true, isRunning: false, lastCheckedAt: null },
+      };
       mockProxyApi.mockResolvedValueOnce(mockHealth);
 
       const result = await fetchRemoteNodeHealth("node_abc");
@@ -44,7 +49,12 @@ describe("api-node", () => {
     });
 
     it("returns remote node health data", async () => {
-      const mockHealth = { status: "offline", version: "2.0.0", nodeId: "node_xyz" };
+      const mockHealth = {
+        status: "offline",
+        version: "2.0.0",
+        nodeId: "node_xyz",
+        database: { healthy: false, isRunning: true, lastCheckedAt: "2026-05-11T10:00:00.000Z" },
+      };
       mockProxyApi.mockResolvedValueOnce(mockHealth);
 
       const result = await fetchRemoteNodeHealth("node_xyz");
@@ -52,6 +62,11 @@ describe("api-node", () => {
       expect(result.status).toBe("offline");
       expect(result.version).toBe("2.0.0");
       expect(result.nodeId).toBe("node_xyz");
+      expect(result.database).toEqual({
+        healthy: false,
+        isRunning: true,
+        lastCheckedAt: "2026-05-11T10:00:00.000Z",
+      });
     });
   });
 

packages/dashboard/app/api-node.ts

@@ -12,6 +12,11 @@ export interface RemoteNodeHealth {
   status: string;
   version: string;
   nodeId: string;
+  database: {
+    healthy: boolean;
+    lastCheckedAt: string | null;
+    isRunning: boolean;
+  };
 }
 
 /** Fetch health information from a remote node */

packages/dashboard/app/api/legacy.ts

@@ -199,6 +199,11 @@ export interface DashboardHealthResponse {
   status: string;
   version: string;
   uptime: number;
+  database: {
+    healthy: boolean;
+    lastCheckedAt: string | null;
+    isRunning: boolean;
+  };
 }
 
 export function fetchDashboardHealth(): Promise<DashboardHealthResponse> {

packages/dashboard/src/__tests__/auth-middleware-integration.test.ts

@@ -66,9 +66,9 @@ class MockStore extends EventEmitter {
 
   getDatabaseHealth() {
     return {
-      corruptionDetected: false,
-      integrityCheckPending: false,
-      integrityCheckLastRunAt: null,
+      healthy: true,
+      isRunning: false,
+      lastCheckedAt: null,
     };
   }
 

packages/dashboard/src/__tests__/server.test.ts

@@ -69,9 +69,9 @@ function createMockStore(overrides: Partial<TaskStore> = {}): TaskStore {
       prepare: vi.fn().mockReturnValue({ run: vi.fn().mockReturnValue({ changes: 0 }), get: vi.fn(), all: vi.fn().mockReturnValue([]) }),
     }),
     getDatabaseHealth: vi.fn().mockReturnValue({
-      corruptionDetected: false,
-      integrityCheckPending: false,
-      integrityCheckLastRunAt: null,
+      healthy: true,
+      isRunning: false,
+      lastCheckedAt: null,
     }),
     getMissionStore: vi.fn().mockReturnValue({
       listMissions: vi.fn().mockReturnValue([]),
@@ -313,9 +313,9 @@ describe("createServer health and headless mode", () => {
       version: CLI_PACKAGE_VERSION,
       uptime: expect.any(Number),
       database: {
-        corruptionDetected: false,
-        integrityCheckPending: false,
-        integrityCheckLastRunAt: null,
+        healthy: true,
+        isRunning: false,
+        lastCheckedAt: null,
       },
     });
   });
@@ -323,9 +323,9 @@ describe("createServer health and headless mode", () => {
   it("reports degraded status when database corruption is detected", async () => {
     const store = createMockStore({
       getDatabaseHealth: vi.fn().mockReturnValue({
-        corruptionDetected: true,
-        integrityCheckPending: false,
-        integrityCheckLastRunAt: "2026-05-11T10:00:00.000Z",
+        healthy: false,
+        isRunning: false,
+        lastCheckedAt: new Date("2026-05-11T10:00:00.000Z"),
       }),
     });
     const app = createServer(store);
@@ -338,9 +338,9 @@ describe("createServer health and headless mode", () => {
       version: CLI_PACKAGE_VERSION,
       uptime: expect.any(Number),
       database: {
-        corruptionDetected: true,
-        integrityCheckPending: false,
-        integrityCheckLastRunAt: "2026-05-11T10:00:00.000Z",
+        healthy: false,
+        isRunning: false,
+        lastCheckedAt: "2026-05-11T10:00:00.000Z",
       },
     });
   });

packages/dashboard/src/server.ts

@@ -1058,7 +1058,7 @@ export function createServer(store: TaskStore, options?: ServerOptions): ReturnT
   app.get("/api/health", (_req, res) => {
     const database = store.getDatabaseHealth();
     res.json({
-      status: database.corruptionDetected ? "degraded" : "ok",
+      status: database.healthy ? "ok" : "degraded",
       version: cliPackageVersion,
       uptime: Math.floor(process.uptime()),
       database,