debt - improve workspace settings and copilot configuration (#255359)

.github/instructions/typescript.instructions.md

@@ -0,0 +1,29 @@
+---
+applyTo: '**/*.ts'
+---
+
+# VS Code Copilot Development Instructions
+
+## ⚠️ MANDATORY COMPILATION CHECK
+
+**CRITICAL: You MUST check compilation output before running ANY script or declaring work complete!**
+
+### Before running any command:
+1. **ALWAYS** check the "Core - Build" task output for compilation errors
+2. **ALWAYS** check the "Ext - Build" task output for compilation errors
+3. **NEVER** run tests if there are compilation errors
+4. **FIX** all compilation errors before moving forward
+
+## Scripts
+- Use `npm install` to install dependencies if you changed `package.json`
+- Use `scripts/test.sh` (or `scripts\test.bat` on Windows) for unit tests (add `--grep <pattern>` to filter tests)
+- Use `scripts/test-integration.sh` (or `scripts\test-integration.bat` on Windows) for integration tests
+- Use `npm run valid-layers-check` to check for layering issues
+
+## Compilation Tasks
+Typescript compilation errors can be found by running the "Core - Build" and "Ext - Build" tasks:
+- **Core - Build**: Compiles the main VS Code TypeScript sources
+- **Ext - Build**: Compiles the built-in extensions
+- These background tasks may already be running from previous development sessions
+- If not already running, start them to get real-time compilation feedback
+- The tasks provide incremental compilation, so they will automatically recompile when files change