2afa4c6ee0
- Add parseRelativeExpression() to detect pattern: attr+/-duration - Add resolveDateValue() to resolve absolute or relative dates - Add applyDateAttribute() helper for date attributes with relative support - Track attribute order in Modifier struct (AttributeOrder field) - Refactor Apply() and ApplyToNew() to process attrs in order - Support chaining: due:mon scheduled:due-3d wait:scheduled-1d - Support addition and subtraction: due+1y, wait-2d - Add comprehensive test suite for relative expressions - Error if referencing undefined date attribute - All 38+ tests passing