Add .prettierignore file (#6914)

.prettierignore

@@ -0,0 +1,20 @@
+**/bundle
+**/coverage
+**/dist
+**/.git
+**/node_modules
+.docker
+.DS_Store
+.env
+.gemini/
+.idea
+.integration-tests/
+*.iml
+*.tsbuildinfo
+*.vsix
+bower_components
+eslint.config.js
+**/generated
+gha-creds-*.json
+junit.xml
+Thumbs.db