fix: Resolve TypeScript compilation errors and test environment issues

- Update interface definitions to match test requirements
- Add missing methods to DailyNotificationPlugin interface
- Fix ContentHandler signature compatibility
- Switch Jest test environment from node to jsdom
- Install required jsdom dependencies
- Update mock plugin objects with all required methods
- Fix timestamp type mismatches in tests

docs/TODO.md

@@ -16,16 +16,17 @@
 - [x] Add proper error handling and logging
 
 ### 1.2 Fix Interface Definitions
-- [ ] Align TypeScript interfaces with project requirements
-- [ ] Add missing properties referenced in tests
-- [ ] Implement proper validation utilities
-- [ ] Create comprehensive error types
-- [ ] Add retry mechanism interfaces
+- [x] Align TypeScript interfaces with project requirements
+- [x] Add missing properties referenced in tests
+- [x] Implement proper validation utilities
+- [x] Create comprehensive error types
+- [x] Add retry mechanism interfaces
 
 ### 1.3 Fix Test Suite
-- [ ] Update all test files to match current interfaces
-- [ ] Implement proper mock objects
-- [ ] Fix TypeScript compilation errors
+- [x] Update all test files to match current interfaces
+- [x] Implement proper mock objects
+- [x] Fix TypeScript compilation errors
+- [ ] Fix test execution issues (plugin registration, validation)
 - [ ] Ensure 100% test coverage
 - [ ] Add integration tests for native platforms