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.

views/settings-v2/tab-general.php

@@ -0,0 +1,123 @@
+<?php
+/**
+ * Settings V2: General.
+ *
+ * @package WP_Agentic_Writer
+ */
+
+if (!defined("ABSPATH")) {
+    exit();
+} ?>
+<div class="section-head">
+	<div>
+		<p class="eyebrow"><?php esc_html_e("Foundation", "wp-agentic-writer"); ?></p>
+		<h2><?php esc_html_e("General settings", "wp-agentic-writer"); ?></h2>
+		<p><?php esc_html_e(
+      "Manage your agent's core identity, clarification limits, and language preferences.",
+      "wp-agentic-writer",
+  ); ?></p>
+	</div>
+</div>
+
+<div class="panel">
+	<div class="panel-head">
+		<div class="panel-title">
+			<h3><?php esc_html_e(
+       "Global Context & Brand Voice",
+       "wp-agentic-writer",
+   ); ?></h3>
+			<p><?php esc_html_e(
+       "Set unbreakable rules, tone, and identity for the AI. This context is injected into every single agentic request.",
+       "wp-agentic-writer",
+   ); ?></p>
+		</div>
+	</div>
+	<div class="panel-body">
+		<div class="field" style="width: 100%;">
+			<textarea class="field-control" id="global_context" name="wp_agentic_writer_settings[global_context]" rows="5" placeholder="<?php esc_attr_e(
+       "e.g., You are a senior attorney writing for a legal blog. Never give direct legal advice. Always use British English. Avoid mentioning competitors.",
+       "wp-agentic-writer",
+   ); ?>" style="width: 100%; font-family: ui-monospace, SFMono-Regular, monospace; resize: vertical;"><?php echo esc_textarea(
+    $global_context ?? "",
+); ?></textarea>
+			<p class="help" style="margin-top: 8px;">
+				<?php esc_html_e(
+        "Think of this as the DNA of your agent. While Memanto learns from user feedback organically, this field defines hard guardrails that the AI must always follow.",
+        "wp-agentic-writer",
+    ); ?>
+			</p>
+		</div>
+	</div>
+</div>
+
+<div class="panel">
+	<div class="panel-head"><div class="panel-title"><h3><?php esc_html_e(
+     "Research & clarification",
+     "wp-agentic-writer",
+ ); ?></h3><p><?php esc_html_e(
+    "Control question generation.",
+    "wp-agentic-writer",
+); ?></p></div></div>
+	<div class="panel-body">
+		<label class="switch-row" style="margin-top:0px"><input type="checkbox" name="wp_agentic_writer_settings[enable_clarification_quiz]" value="1" <?php checked(
+      $enable_clarification_quiz,
+  ); ?>><span class="switch"></span><span><?php esc_html_e(
+    "Ask clarification quiz before writing",
+    "wp-agentic-writer",
+); ?></span></label>
+	</div>
+</div>
+
+<div class="panel">
+	<div class="panel-head"><div class="panel-title"><h3><?php esc_html_e(
+     "Language preferences",
+     "wp-agentic-writer",
+ ); ?></h3><p><?php esc_html_e(
+    "Preferred writing languages and chat memory limits.",
+    "wp-agentic-writer",
+); ?></p></div></div>
+	<div class="panel-body grid-2">
+		<div class="field"><label for="chat_history_limit"><?php esc_html_e(
+      "Chat history limit",
+      "wp-agentic-writer",
+  ); ?></label><input class="field-control" type="number" min="1" id="chat_history_limit" name="wp_agentic_writer_settings[chat_history_limit]" value="<?php echo esc_attr(
+    $chat_history_limit,
+); ?>"></div>
+		<div class="field"><label for="clarity_confidence_threshold"><?php esc_html_e(
+      "Clarity threshold",
+      "wp-agentic-writer",
+  ); ?></label><select class="field-control" id="clarity_confidence_threshold" name="wp_agentic_writer_settings[clarity_confidence_threshold]"><option value="0.4" <?php selected(
+    $clarity_confidence_threshold,
+    "0.4",
+); ?>>Relaxed</option><option value="0.6" <?php selected(
+    $clarity_confidence_threshold,
+    "0.6",
+); ?>>Balanced</option><option value="0.8" <?php selected(
+    $clarity_confidence_threshold,
+    "0.8",
+); ?>>Strict</option></select></div>
+		<div class="field language-field"><label for="preferred_languages"><?php esc_html_e(
+      "Preferred languages",
+      "wp-agentic-writer",
+  ); ?></label><select class="field-control" id="preferred_languages" name="wp_agentic_writer_settings[preferred_languages][]" multiple><?php foreach (
+    (array) $available_languages
+    as $language_value => $language_label
+): ?><option value="<?php echo esc_attr($language_value); ?>" <?php selected(
+    in_array($language_value, (array) $preferred_languages, true),
+); ?>><?php echo esc_html(
+    $language_label,
+); ?></option><?php endforeach; ?></select><p class="help"><?php esc_html_e(
+    "These are passed to the editor language controls.",
+    "wp-agentic-writer",
+); ?></p></div>
+		<div class="field"><label for="custom_languages"><?php esc_html_e(
+      "Custom languages",
+      "wp-agentic-writer",
+  ); ?></label><input class="field-control" type="text" id="custom_languages" name="wp_agentic_writer_settings[custom_languages][]" value="<?php echo esc_attr(
+    implode(", ", (array) $custom_languages),
+); ?>" placeholder="Javanese, Sundanese"><p class="help"><?php esc_html_e(
+    "Separate multiple custom languages with commas.",
+    "wp-agentic-writer",
+); ?></p></div>
+	</div>
+</div>