feat(vscode): add Biome auto-fix on save configuration (#26839)

Replace ESLint fixAll with Biome codeActionsOnSave settings:
- source.fixAll.biome: applies safe lint fixes (e.g., removing unused imports)
- source.organizeImports.biome: sorts and organizes imports/exports

Both are needed separately because they serve different purposes:
- fixAll handles lint rule auto-fixes
- organizeImports handles import sorting/ordering

This aligns with Biome being the default formatter in this repo.

Co-authored-by: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

.vscode/settings.json

@@ -3,7 +3,8 @@
   "editor.formatOnSave": true,
   "editor.defaultFormatter": "biomejs.biome",
   "editor.codeActionsOnSave": {
-    "source.fixAll.eslint": "explicit"
+    "source.fixAll.biome": "explicit",
+    "source.organizeImports.biome": "explicit"
   },
   "typescript.preferences.importModuleSpecifier": "non-relative",
   "spellright.language": ["en"],