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.

includes/class-context-builder.php

@@ -370,6 +370,14 @@ class WP_Agentic_Writer_Context_Builder
             "BACKEND CONTINUITY CONTEXT\nUse this compact WordPress-saved context as continuity. Do not assume OpenRouter remembers prior turns.";
         $sections[] = "Current task: " . sanitize_key($task);
 
+        // Global brand voice / context injection
+        $settings = get_option("wp_agentic_writer_settings", []);
+        $global_context = trim($settings["global_context"] ?? "");
+        if ("" !== $global_context) {
+            $sections[] =
+                "GLOBAL SITE CONTEXT (CRITICAL RULES):\n" . $global_context;
+        }
+
         // MEMANTO persistent memory injection.
         $memanto_context = $this->build_memanto_context(
             $post_id,