#8416 Regenerate stale diff viewer bundle

Summary

• regenerate the committed diff viewer chunk from the current webviews sources
• restore react-apps-check on current main without changing source behavior

Testing

• reproduced ./scripts/build-webviews-app.sh --check failing only for Resources/markdown-viewer/webviews-app/chunks/diffSurface.mjs
• verified fresh regeneration matches Austin Wang's standalone commit 1ad4076806cb8e35a2c31ff5a52c24e87d15c235 byte for byte
• ./scripts/build-webviews-app.sh --check
• ./scripts/check-webviews-react-compiler.mjs
• cd webviews && bun run typecheck
• cd webviews && bun run test (230 passed)
• cd webviews && bun run lint:ci
• cd webviews && bun run react-doctor:ci
• git diff --check

Issues

• Related: https://github.com/manaflow-ai/cmux/pull/7804
• Source commit: https://github.com/manaflow-ai/cmux/commit/1ad4076806cb8e35a2c31ff5a52c24e87d15c235

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Summary by cubic

Regenerated the stale diff viewer bundle Resources/markdown-viewer/webviews-app/chunks/diffSurface.mjs to sync with current webviews sources and unblock react-apps-check on main. No source or runtime changes.

• Bug Fixes
  • Rebuilt the bundle with ./scripts/build-webviews-app.sh to match current webviews code and prevent drift.
  • Ensures webviews build and React compiler checks pass again.