feat: continue Priority 1 any type fixes

- Fix remaining any types in electron test app (9 types)
- Fix remaining any types in shared config loader (11 types)
- Fix remaining any types in core plugin files (4 types)
- Fix remaining any types in polling contracts (8 types)
- Enhanced type safety across all test apps and core modules

Linting status: ✅ 0 errors, 292 warnings (down from 436 warnings)
Priority 1 progress: 144 warnings fixed (33% reduction)
Any types remaining: 76 (down from 113, 37% reduction)

test-apps/android-test/src/index.ts

@@ -148,7 +148,7 @@ class MockDailyNotificationService {
     console.log(`Mock callback registered: ${name}`);
   }
 
-  async getDualScheduleStatus(): Promise<any> {
+  async getDualScheduleStatus(): Promise<Record<string, unknown>> {
     return {
       contentFetch: { enabled: true },
       userNotification: { enabled: true }