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.

vendor/nikic/php-parser/lib/PhpParser/Node/Arg.php

@@ -0,0 +1,44 @@
+<?php declare(strict_types=1);
+
+namespace PhpParser\Node;
+
+use PhpParser\NodeAbstract;
+
+class Arg extends NodeAbstract {
+    /** @var Identifier|null Parameter name (for named parameters) */
+    public ?Identifier $name;
+    /** @var Expr Value to pass */
+    public Expr $value;
+    /** @var bool Whether to pass by ref */
+    public bool $byRef;
+    /** @var bool Whether to unpack the argument */
+    public bool $unpack;
+
+    /**
+     * Constructs a function call argument node.
+     *
+     * @param Expr $value Value to pass
+     * @param bool $byRef Whether to pass by ref
+     * @param bool $unpack Whether to unpack the argument
+     * @param array<string, mixed> $attributes Additional attributes
+     * @param Identifier|null $name Parameter name (for named parameters)
+     */
+    public function __construct(
+        Expr $value, bool $byRef = false, bool $unpack = false, array $attributes = [],
+        ?Identifier $name = null
+    ) {
+        $this->attributes = $attributes;
+        $this->name = $name;
+        $this->value = $value;
+        $this->byRef = $byRef;
+        $this->unpack = $unpack;
+    }
+
+    public function getSubNodeNames(): array {
+        return ['name', 'value', 'byRef', 'unpack'];
+    }
+
+    public function getType(): string {
+        return 'Arg';
+    }
+}