test: sync record member keyword fixtures

[mjq2020]

Summary

• add the C# record member names clone, equalityContract, and printMembers to test/keywords.txt
• regenerate all three keyword fixtures with test/make-keyword-tests.sh
• restore byte-for-byte reproducibility between the generator input and checked-in outputs

Root cause

PR #3078 added the three names directly to keywords.json, but not to the source list consumed by keywords.py. Running the documented generator therefore removed those cases. Adding them to keywords.txt keeps the JSON, enum schema, and union schema in sync. The small object-boundary reshuffle in keywords.json is expected because the generator splits the ordered list into groups of 64.

Tests

• byte-for-byte regeneration check for all three generated files
• npm run build
• npm run test:unit (52 files, 236 tests)
• npm run lint -- --no-errors-on-unmatched
• focused keywords.json fixture tests for JavaScript, TypeScript, Python, PHP, and Go

Fixes #3120