feat(feedback): personal AI models, AI run tracking and profiles/options endpoint

- user_settings allowlist: feedback_models (up to 10 personal model configs)
- normalizeFeedbackModels() validation, UI block "Мои модели" in #fbPromptModal
- GET /api/ai/profiles/options for tutors (no api_key), used by feedback/shorts
- feedbacks columns ai_prompt/ai_model/ai_duration_ms + backup/restore support
- "ИИ-запрос" popover on feedback card with status, model, timing and prompt
- audit: feedback.update / feedback.ai.run / feedback.ai.error labels

db/init.sql

@@ -529,6 +529,9 @@ CREATE TABLE IF NOT EXISTS feedbacks (
   ai_checked_at TIMESTAMPTZ,
   ai_error TEXT,
   ai_profile VARCHAR(100),
+  ai_prompt TEXT,
+  ai_model VARCHAR(200),
+  ai_duration_ms INT,
   sent_at TIMESTAMPTZ,
   author_id INT REFERENCES users(id) ON DELETE SET NULL,
   branch_id INT REFERENCES branches(id) ON DELETE SET NULL,