feat(system): enable window destroy capability and stabilize shutdown

Adds a new window capability to allow destroying the window.
It also changes shutdown handling in telemetry to avoid errors.

- Add core:window:allow-destroy to default capabilities
- Avoid shutdown errors by returning a pending promise in tracedInvoke
- Improve stability during shutdown for in-flight telemetry calls

src-tauri/capabilities/default.json

@@ -9,6 +9,7 @@
     "core:window:allow-toggle-maximize",
     "core:window:allow-unminimize",
     "core:window:allow-close",
+    "core:window:allow-destroy",
     "core:window:allow-is-maximized",
     "core:window:allow-start-dragging",
     "dialog:allow-open",

src/lib/telemetry.ts

@@ -48,7 +48,12 @@ function randomHex(bytes: number): string {
 
 export async function tracedInvoke<T>(command: string, args?: Record<string, unknown>): Promise<T> {
   if (frontendShuttingDown) {
-    throw new Error("Application is shutting down");
+    // The window is on its way out and nothing calls preventDefault() on the
+    // close event, so it will finish closing regardless. Never resolving
+    // avoids surfacing a spurious "shutting down" error in whatever UI catch
+    // block happens to be awaiting an in-flight operation (e.g. a pull/push
+    // that makes several sequential calls) when the close request lands.
+    return new Promise<T>(() => {});
   }
   if (!telemetryEnabled) return invoke<T>(command, args);
   const startedAtMs = Date.now();