Fixes critical metadata index file pollution bug that created 358k garbage files.
Changes:
- Remove timestamps from excludeFields to enable indexing and range queries
- Auto-detect temporal fields by name (time/date/accessed/modified/created/updated)
- Bucket temporal values to 1-minute intervals to prevent pollution
- Fix all normalizeValue() calls to pass field parameter for bucketing
Results:
- File reduction: 360k → 4.6k files (98.7% reduction)
- Range queries now work: modified >= yesterday
- Zero configuration required
- Backward compatible with existing code
Test coverage:
- 10 comprehensive tests for automatic bucketing
- All tests passing with bucket-aligned timestamps
- Covers file pollution prevention, range queries, field detection
