fix(lsp): prevent stale diagnostics by syncing didChange

[Zacks-Zhang]

Summary

• Fix stale LSP diagnostics by syncing updated on-disk file contents to the language server after edits.
• Add a focused unit test to ensure a previously opened file triggers a content update notification.

Changes

• Updated src/tools/lsp/client.ts to:
  • Track per-document version numbers and last-synced text.
  • Send textDocument/didChange (full text) when a file that was already didOpen’d changes on disk.
  • Send textDocument/didSave after didChange to improve compatibility with servers that refresh diagnostics on save.
• Added src/tools/lsp/client.test.ts to verify didChange is emitted when a previously opened file’s content changes.

Testing

bun run typecheck
bun test src/tools/lsp/*.test.ts

Related Issues

#1272

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Summary by cubic

Fixes stale LSP diagnostics by syncing file changes for already-opened files via didChange and didSave. Addresses #1272.

• Bug Fixes
  • Track per-document version and last-synced text.
  • Emit textDocument/didChange (full text) when an opened file’s content changes on disk.
  • Emit textDocument/didSave after didChange for servers that refresh on save.
  • Add a unit test that asserts didChange is sent for a previously opened file.

^{Written for commit 3bb4289. Summary will update on new commits.}

[github-actions]

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[Zacks-Zhang]

I have read the CLA Document and I hereby sign the CLA

[cubic-dev-ai]

No issues found across 2 files

Confidence score: 5/5

• Automated review surfaced no issues in the provided summaries.
• No files require special attention.