chore: align repo structure with plugin conventions

Add missing config files (.eslintrc.js, .prettierrc.js, .pluginrc,
.mcp.json, renovate.json), documentation (CLAUDE.md, CONTRIBUTING.md,
README.md, SECURITY.md, LICENSE), CI/CD workflows (ci.yaml, release.yaml),
and Claude agent definitions. Rename package from headlamp-intel-gpu-plugin
to intel-gpu to match the short-name convention used by all other plugins.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

CONTRIBUTING.md

@@ -0,0 +1,36 @@
+# Contributing
+
+Contributions are welcome! Please follow these guidelines.
+
+## Development Setup
+
+```bash
+git clone https://github.com/privilegedescalation/headlamp-intel-gpu-plugin.git
+cd headlamp-intel-gpu-plugin
+npm install
+npm start
+```
+
+## Before Submitting a PR
+
+```bash
+npm run tsc          # TypeScript type check
+npm run lint         # ESLint
+npm run format:check # Prettier
+npm test             # All tests must pass
+```
+
+## Code Style
+
+- TypeScript strict mode (no `any`)
+- Functional React components only
+- All UI from `@kinvolk/headlamp-plugin/lib/CommonComponents`
+- Tests with vitest + @testing-library/react
+
+## Commit Messages
+
+Use conventional commit format:
+- `feat:` new features
+- `fix:` bug fixes
+- `chore:` maintenance
+- `docs:` documentation