docs: consolidate CLAUDE.md and CONTRIBUTING.md, add style guidelines

- Refactor CLAUDE.md to reference CONTRIBUTING.md for build/test/format info
- Expand CONTRIBUTING.md with comprehensive build targets, env vars, and testing
- Add code style guidelines section with conventional commits
- Standardize SDK prettier config to use single quotes (matching web)
- Add project-level Claude Code settings to disable co-author attribution

sdk/base/package.json

@@ -34,7 +34,7 @@
     "trailingComma": "all",
     "tabWidth": 2,
     "semi": false,
-    "singleQuote": false
+    "singleQuote": true
   },
   "devDependencies": {
     "@types/jest": "^29.4.0",