test: add Phase 1 & 2 tests (data integrity + entry lifecycle)

Phase 1 - Data Integrity (#96):
- validators.test.ts: 54 tests for validateSerializedData
- persistence.test.ts: 22 tests for file load/save operations
- types.test.ts: Extended with comprehensive type guards, equality,
  merging, and factory function tests

Phase 2 - Entry Lifecycle (#97):
- entryCrud.test.ts: 32 tests for entry creation, deletion, resolution
- locations.test.ts: 42 tests for location management and selection
- auditing.test.ts: 42 tests for file auditing and partial audits

Total: 311 tests passing

Closes #96, Closes #97

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: fegge