feat: add Deepbrid, daily scheduling, and notification center

Add encrypted Deepbrid API accounts with account validation, provider routing, fallback, usage tracking, safe error handling, and verified 1Fichier downloads. Restore persistent recurring daily starts with local-calendar deduplication and legacy schedule compatibility. Add durable Discord package, run, remaining-volume, stall, and recovery notifications with privacy-safe telemetry and disk-failure recovery.

tests/renderer-state.test.ts

@@ -40,6 +40,18 @@ const ACCOUNT_FIXTURES: Array<{
 ];
 
 describe("renderer state serialization", () => {
+  it("projects notification controls with their safe defaults", () => {
+    expect(createRendererState(defaultSettings()).settings).toEqual(expect.objectContaining({
+      notifyPackageSuccessMode: "digest",
+      notifyOnRemainingBelow: false,
+      notifyRemainingThresholdGb: 50,
+      notifyOnDownloadStall: false,
+      notifyStallAfterSeconds: 90,
+      notifyStallCooldownMinutes: 10,
+      notifyOnDownloadRecovery: true
+    }));
+  });
+
   it("projects distinct Real-Debrid API and Web rows with per-account state", () => {
     const firstToken = "fixture-renderer-rd-first-1aB2";
     const secondToken = "fixture-renderer-rd-second-3cD4";