chore: fix lint errors and reduce warnings across codebase (#234)

* chore: fix lint errors and reduce warnings across codebase

- Fix noExplicitAny catches in backend routes and plugins
- Fix noNestedTernary issues in backend services
- Add keyboard event handlers for useKeyWithClickEvents in frontend
- Disable noImportantStyles rule in biome.json
- Fix formatting errors across all changed files
- Fix test file lint issues

Closes #233

* fix: restore any types in test files for TS compatibility

* fix: revert Auth.tsx dependency array changes that caused infinite re-render

* fix: null-safe user.username access in AppContext dependency array

backend/src/test/planner.test.ts

@@ -63,7 +63,7 @@ vi.mock("../services/reminder-scheduler.js", () => ({
 
 // Mock sendShoutrrrNotification from settings
 vi.mock("../routes/settings.js", async (importOriginal) => {
-	const original = (await importOriginal()) as any;
+	const original = (await importOriginal()) as Record<string, unknown>;
 	return {
 		...original,
 		sendShoutrrrNotification: mockSendShoutrrr,