feat: Brainstorm Topics with GSC + Issue #518 fixes + Blog Editor enhancements

Issue #518 - Subscription not updating after checkout:
- Fix stale closure in SubscriptionContext checkout polling (use subscriptionRef)
- Move checkout success polling from InitialRouteHandler into SubscriptionContext
- Remove redundant polling code from InitialRouteHandler
- Fix plan label: 'Free' instead of 'No Plan', proper capitalization
- Add plan refresh button in UserBadge
- Add 'View Costing Details' to UserBadge dropdown
- Rename 'ALwrity Podcast Maker' to 'Podcast Creator' across UI
- Clean subscription=success URL param after verification

Blog Writer WYSIWYG Editor enhancements:
- Per-section preview toggle (view/edit icons)
- Enhanced hover-based toolbar
- Circular SVG progress stats bar with detailed tooltip
- Research tool chips in stats bar footer
- Per-section TTS with useTextToSpeech hook (browser native)
- Full blog preview modal with print/PDF support
- PlayAllTTSButton: sequential playback with progress bar
- OnThisPageNav: floating sidebar with scroll tracking
- Section data attributes for scroll anchoring

GSC Brainstorm Topics feature:
- Backend: gsc_brainstorm_service.py (rule-based + LLM recommendations)
- Backend: POST /gsc/brainstorm endpoint with 3-word minimum validation
- Frontend: gscBrainstorm.ts API client
- Frontend: useGSCBrainstormConnection hook (popup OAuth, no /onboarding redirect)
- Frontend: useGSCBrainstorm hook (connect check + brainstorm call)
- Frontend: GSCBrainstormModal (3-tab results: Opportunities, Gaps, AI Recs)
- Frontend: BrainstormButton (visible at 3+ words, GSC connect overlay)
- Wire BrainstormButton into ManualResearchForm and ResearchAction
- Add blog_writer to gsc_auth router features for ALWRITY_ENABLED_FEATURES

backend/services/integrations/wix/blog.py

@@ -53,6 +53,7 @@ class WixBlogService:
         """Create draft post with consolidated logging"""
         from .logger import wix_logger
         import json
+        import traceback as tb
         
         # Build payload summary for logging
         payload_summary = {}
@@ -65,7 +66,14 @@ class WixBlogService:
             }
         
         request_headers = self.headers(access_token, extra_headers)
-        response = requests.post(f"{self.base_url}/blog/v3/draft-posts", headers=request_headers, json=payload)
+        try:
+            response = requests.post(f"{self.base_url}/blog/v3/draft-posts", headers=request_headers, json=payload)
+        except TypeError as e:
+            logger.error(f"TypeError during requests.post in create_draft_post: {e}")
+            logger.error(f"Traceback: {tb.format_exc()}")
+            logger.error(f"access_token type: {type(access_token)}")
+            logger.error(f"payload type: {type(payload)}, keys: {list(payload.keys()) if isinstance(payload, dict) else 'N/A'}")
+            raise
         
         # Consolidated error logging
         error_body = None