Phase 74 implements BindingId as parallel allocation alongside ValueId for
lexical scope tracking and shadowing-aware variable identity.
Changes:
- binding_id.rs: New BindingId type with overflow protection (5 unit tests)
- builder.rs: Added next_binding_id counter and binding_map (4 integration tests)
- lexical_scope.rs: Extended restoration logic for BindingId management
- mod.rs: Public re-export of BindingId
Tests: 9/9 new PASS, lib 958/958 PASS (no regressions)
Architecture: Parallel BindingId/ValueId allocation for deterministic shadowing
Phase 75-77 will build on this infrastructure for type-safe promotion tracking.
🤖 Generated with Claude Code
Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>
