feat(codemode): complete regexp and math parity

[rekram1-node]

Summary

• expose RegExp.escape, hasIndices, unicodeSets, and d-flag match indices across exec, match, and matchAll
• add Math.sumPrecise for supported collection iterables with native precision and strict number validation
• close the RegExp and Math support-matrix gaps with Test262-derived coverage

Testing

• bun test (938 passed)
• bun typecheck
• Prettier check
• git diff --check