Summary

• distinguish canonical array indexes from ordinary own properties
• preserve own-only array reads and writes without invoking inherited accessors
• fix sparse reduce/reduceRight initialization and findLast mutation semantics

Testing

• bun test (packages/codemode): 788 passed
• bun typecheck (packages/codemode)
• repository pre-push typecheck: 31 tasks passed
• Prettier and git diff checks

Review

• reviewed by multiple independent general agents for JavaScript parity, confinement, and test coverage
• addressed inherited property/accessor findings before opening