GocciaScript bytecode VM unification

Date: 2026-03-23 → 2026-04-10 Area: bytecode Pull Requests: #107 #109 #110 #136 #137 #254

VM unification. Fold the separate Souffle VM into a GocciaScript-specific bytecode VM: eliminate interpreter bridges for modules (#107) and async/await (#110), add native-value-backed Map/Set (#109), refactor built-in object model registration (#136), fold the VM directly (#137), and extract the GC into a standalone Goccia.GarbageCollector unit (#254). bytecode-vm.md § Design Rationale. garbage-collector.md.