fix: harden account rotation and active download recovery

Apply account enablement changes optimistically and persist rapid toggles sequentially without losing clicks.

Refresh Mega-Debrid API and Web account pools during active downloads, isolate per-account cancellation budgets, rotate within the same conversion attempt, and keep pause, stop, resume, reset, and no-account gates consistent.

Use the native Electron clipboard under Remote Desktop and make support bundle export bounded, redacted, responsive, guarded, visible, and atomic.

Add end-to-end regressions for live account switching, persisted partial recovery, support export, native copy, availability preservation, and the 500 ms telemetry cadence.

tests/account-preload.test.ts

@@ -61,4 +61,15 @@ describe("account preload contract", () => {
       IPC_CHANNELS.DELETE_ACCOUNT
     ]);
   });
+
+  it("writes copied text through the native Electron clipboard channel", async () => {
+    electron.invoke.mockResolvedValueOnce(true);
+
+    await electron.api?.writeClipboardText("https://rapidgator.net/file/example");
+
+    expect(electron.invoke).toHaveBeenCalledWith(
+      IPC_CHANNELS.WRITE_CLIPBOARD_TEXT,
+      "https://rapidgator.net/file/example"
+    );
+  });
 });