fix: WYSIWYG editor, content generation, and writing assistant bug fixes

- Fix text selection menu not showing: wire contentRef via inputRef on multiline TextField
- Fix blog title not truncating: add min-w-0 for flex item overflow
- Fix outline generation 500: escape curly braces in f-string prompt template
- Fix content generation 'NoneType not callable': replace SessionLocal() with get_session_for_user(), add db param to MediumBlogGenerator, fix signature mismatch in database_task_manager
- Fix writing assistant suggest 500: add auth + user_id to API endpoint and service, replace sync requests with httpx.AsyncClient
- Fix hallucination detector 404: explicitly include router in main.py and app.py
- Fix missing error_data in task failure responses
- Hide CopilotKit web inspector button
- Remove hardcoded fallback suggestions from SmartTypingAssist
- Fix stale closure refs in SmartTypingAssist handleTypingChange
- Add two-column editor layout, stats bar, section hover menu
- Various subscription, billing, and research module improvements

backend/services/subscription/usage_tracking_modules/usage_trends.py

@@ -0,0 +1,18 @@
+"""
+Usage trends functions.
+Extracted from usage_tracking_service.py for better maintainability.
+"""
+
+from typing import Dict, Any
+from sqlalchemy.orm import Session
+from loguru import logger
+
+        
+def get_usage_trends(user_id: str, months: int, db: Session) -> Dict[str, Any]:
+    """Get usage trends over time with self-healing from logs."""
+    from services.subscription.usage_tracking_helpers import build_billing_periods, query_usage_summaries, self_heal_summaries_from_logs, build_usage_trends_response
+    
+    periods = build_billing_periods(months)
+    summary_dict = query_usage_summaries(db, user_id, periods)
+    self_heal_summaries_from_logs(db, user_id, periods, summary_dict)
+    return build_usage_trends_response(periods, summary_dict)