[Phalgun Vaddepalli (phalgunv)]

Summary

Add a self-contained sample extension demonstrating the VS Code DiagnosticCollection API.

The sample:

• Publishes error, warning, and information diagnostics from marker lines.
• Updates diagnostics as the demo document changes.
• Demonstrates set, get, has, forEach, delete, and clear.
• Includes commands for scanning, clearing, and inspecting the collection.
• Uses an isolated test-workspace so F5 does not reopen the main workspace in the Extension Development Host.

Also updates the repository sample index and uses non-deprecated TypeScript module resolution for the repository tooling.

Validation

• npm --prefix diagnostic-collection-sample run compile
• npm --prefix diagnostic-collection-sample run lint
• npx tsc --noEmit -p .scripts/tsconfig.json
• npm run validate

[Phalgun Vaddepalli (phalgunv)]

@microsoft-github-policy-service agree