refactor: Cleanup git state - commit all staged changes

Major refactoring cleanup:
- Add new controller architecture (class-controller-*.php)
- Add new settings-v2 UI (views/settings-v2/)
- Add new CSS architecture (agentic-sidebar.css, tokens)
- Add esbuild build pipeline (scripts/build.js, package.json)
- Add composer dependencies (vendor/)
- Add frontend src directory (assets/js/src/index.jsx)
- Add documentation files
- Remove old/obsolete files (class-settings.php, old CSS)

This commits all pending changes from previous refactoring efforts.

tsconfig.sidebar.json

@@ -0,0 +1,13 @@
+{
+  "compilerOptions": {
+    "allowJs": true,
+    "checkJs": false,
+    "jsx": "react",
+    "jsxFactory": "wp.element.createElement",
+    "jsxFragmentFactory": "wp.element.Fragment",
+    "module": "none",
+    "target": "ESNext",
+    "outFile": "assets/js/dist/sidebar.js"
+  },
+  "files": ["assets/js/src/index.jsx"]
+}