Ship persona shelves, Exact controls, and overlay author pipeline.

Add Leonid as a shelf-based example with preference_bias slider; support /persona new clone-to-overlay and UI-only delete.

Co-authored-by: Cursor <cursoragent@cursor.com>

Tabs/Text2Image/Assistent.html

@@ -55,9 +55,13 @@
                     <div class="sa-chats-panel-hint">Старт = всегда новый чат. Клик по чату восстанавливает сообщения и параметры Generate.</div>
                 </div>
                 <div class="sa-header-right">
-                    <select id="sa_persona" class="sa-select" title="Характер / тон">
-                        <option value="neutral">Нейтральный</option>
-                    </select>
+                    <div class="sa-persona-wrap">
+                        <select id="sa_persona" class="sa-select" title="Характер / тон">
+                            <option value="neutral">Нейтральный</option>
+                        </select>
+                        <button type="button" class="basic-button sa-icon-btn" id="sa_persona_delete" title="Удалить overlay-личность" hidden aria-label="Удалить личность">✕</button>
+                    </div>
+                    <div class="sa-persona-controls" id="sa_persona_controls" hidden></div>
                     <select id="sa_pack" class="sa-select" title="Пакет промпта">
                         <option value="write_prompt">Написать промпт</option>
                     </select>