fix(FN-771): reset disclosure state on task creation and preserve terminal sessions across reconnects

- Reset isDisclosureExpanded in QuickEntryBox resetForm so disclosure collapses after task creation
- Remove sticky disclosure persistence from QuickEntryBox component
- Preserve terminal sessions across transient WebSocket disconnects with buffer/replay
- Buffer and replay initial terminal state for prompt visibility on reconnect
- Update tests for non-persistent disclosure, terminal reconnect, and server routes
- Remove unused UsageIndicator tests and TaskDetailModal test cleanup

packages/dashboard/src/routes.test.ts

@@ -4922,10 +4922,9 @@ describe("Terminal session routes", () => {
 });
 
 describe("Terminal WebSocket close handler", () => {
-  it("kills PTY session when WebSocket closes", async () => {
-    // This tests the server.ts close handler logic by verifying that
-    // setupTerminalWebSocket's close handler calls killSession.
-    // We import server.ts and mock the terminal service.
+  it("does NOT kill PTY session when WebSocket closes (session persists for reconnect)", async () => {
+    // After FN-762, closing a WebSocket must not destroy the PTY session.
+    // The session survives transient disconnects and modal close/reopen cycles.
     const killSessionMock = vi.fn().mockReturnValue(true);
     const getSessionMock = vi.fn().mockReturnValue({
       id: "term-ws-test",
@@ -4949,7 +4948,6 @@ describe("Terminal WebSocket close handler", () => {
 
     vi.spyOn(terminalServiceModule, "getTerminalService").mockReturnValue(mockService as any);
 
-    // Dynamically import to get fresh module with the mock
     const { setupTerminalWebSocket } = await import("./server.js");
 
     const app = express();
@@ -4973,12 +4971,13 @@ describe("Terminal WebSocket close handler", () => {
 
     ws.close();
 
-    expect(killSessionMock).toHaveBeenCalledWith("term-ws-test");
+    // The session must NOT be killed on WebSocket close
+    expect(killSessionMock).not.toHaveBeenCalled();
 
     vi.restoreAllMocks();
   });
 
-  it("kills PTY session when WebSocket encounters an error", async () => {
+  it("does NOT kill PTY session when WebSocket encounters an error (session persists for reconnect)", async () => {
     const killSessionMock = vi.fn().mockReturnValue(true);
     const getSessionMock = vi.fn().mockReturnValue({
       id: "term-ws-err",
@@ -5024,7 +5023,67 @@ describe("Terminal WebSocket close handler", () => {
 
     ws.emit("error", new Error("synthetic websocket failure"));
 
-    expect(killSessionMock).toHaveBeenCalledWith("term-ws-err");
+    // The session must NOT be killed on WebSocket error
+    expect(killSessionMock).not.toHaveBeenCalled();
+
+    vi.restoreAllMocks();
+  });
+
+  it("cleans up data/exit subscriptions on WebSocket close without killing session", async () => {
+    // Verify that WebSocket close properly unsubscribes from terminal service
+    // events without destroying the underlying PTY session.
+    const killSessionMock = vi.fn().mockReturnValue(true);
+    const dataUnsub = vi.fn();
+    const exitUnsub = vi.fn();
+    const getSessionMock = vi.fn().mockReturnValue({
+      id: "term-ws-unsub",
+      shell: "/bin/zsh",
+      cwd: "/test/project",
+    });
+    const getScrollbackAndClearPendingMock = vi.fn().mockReturnValue(null);
+    const onDataMock = vi.fn().mockReturnValue(dataUnsub);
+    const onExitMock = vi.fn().mockReturnValue(exitUnsub);
+
+    const mockService = {
+      getSession: getSessionMock,
+      getScrollbackAndClearPending: getScrollbackAndClearPendingMock,
+      killSession: killSessionMock,
+      write: vi.fn(),
+      resize: vi.fn(),
+      onData: onDataMock,
+      onExit: onExitMock,
+    };
+
+    vi.spyOn(terminalServiceModule, "getTerminalService").mockReturnValue(mockService as any);
+
+    const { setupTerminalWebSocket } = await import("./server.js");
+
+    const app = express();
+    const server = http.createServer(app);
+
+    setupTerminalWebSocket(app, server);
+    class FakeWebSocket extends EventEmitter {
+      send = vi.fn();
+      close = vi.fn(() => this.emit("close"));
+      terminate = vi.fn();
+    }
+
+    const ws = new FakeWebSocket();
+    const wss = (app as express.Express & { terminalWsServer?: EventEmitter }).terminalWsServer;
+    expect(wss).toBeTruthy();
+
+    wss!.emit("connection", ws, {
+      url: "/api/terminal/ws?sessionId=term-ws-unsub",
+      headers: { host: "127.0.0.1" },
+    });
+
+    ws.close();
+
+    // Subscriptions should be cleaned up
+    expect(dataUnsub).toHaveBeenCalled();
+    expect(exitUnsub).toHaveBeenCalled();
+    // But session should NOT be killed
+    expect(killSessionMock).not.toHaveBeenCalled();
 
     vi.restoreAllMocks();
   });

packages/dashboard/src/server.ts

@@ -461,12 +461,10 @@ export function setupTerminalWebSocket(
       clearInterval(pingInterval);
       if (dataUnsub) dataUnsub();
       if (exitUnsub) exitUnsub();
-      // Kill the PTY session to prevent session leaks
-      try {
-        terminalService.killSession(sessionId);
-      } catch {
-        // Ignore errors during cleanup — session may already be dead
-      }
+      // Do NOT kill the PTY session on WebSocket close — the session should
+      // survive transient disconnects and modal close/reopen cycles.  Sessions
+      // are cleaned up through explicit kill paths (tab close, restart, shell
+      // exit) or stale-session eviction.
     });
 
     ws.on("error", () => {
@@ -474,15 +472,28 @@ export function setupTerminalWebSocket(
       clearInterval(pingInterval);
       if (dataUnsub) dataUnsub();
       if (exitUnsub) exitUnsub();
-      // Kill the PTY session to prevent session leaks
-      try {
-        terminalService.killSession(sessionId);
-      } catch {
-        // Ignore errors during cleanup — session may already be dead
-      }
+      // Do NOT kill the PTY session on WebSocket error — same rationale as
+      // close: the session should persist for reconnection attempts.
     });
   });
 
+  // Periodic stale-session eviction (every 60 s) so that PTY sessions are
+  // eventually cleaned up when clients disconnect permanently without going
+  // through explicit kill paths.  The eviction threshold is defined by
+  // TerminalService (default 5 minutes of inactivity).
+  const staleEvictionInterval = setInterval(() => {
+    try {
+      terminalService.evictStaleSessions();
+    } catch {
+      // Ignore errors during periodic eviction
+    }
+  }, 60_000);
+
+  // Stop eviction timer when the server shuts down
+  server.once("close", () => {
+    clearInterval(staleEvictionInterval);
+  });
+
   console.log("Terminal WebSocket server mounted at /api/terminal/ws");
 }