fix: Add missing columns to daily_workflow_plans table

- Added generation_mode column (VARCHAR, default: 'llm_generation')
- Added committee_agent_count column (INTEGER, default: 0)
- Added fallback_used column (BOOLEAN, default: 0)

Also fixed:
- Imported daily_workflow_models in services/database.py to ensure models are registered
- Added _create_daily_workflow_tables() to database setup
- Created migration script to add columns to 35 existing databases
- Fixed WorkflowError type in frontend to use constructor for proper 'name' property

This resolves the 'no such column' sqlite3 errors when accessing the today-workflow API.

backend/services/database.py

@@ -22,6 +22,8 @@ from models.persona_models import Base as PersonaBase
 from models.subscription_models import Base as SubscriptionBase
 from models.user_business_info import Base as UserBusinessInfoBase
 from models.content_asset_models import Base as ContentAssetBase
+# Import daily workflow models to ensure they are registered with EnhancedStrategyBase
+from models.daily_workflow_models import DailyWorkflowPlan, DailyWorkflowTask, TaskHistory
 # Product Marketing models use SubscriptionBase, but import to ensure models are registered
 from models.product_marketing_models import Campaign, CampaignProposal, CampaignAsset
 # Product Asset models (Product Marketing Suite - product assets, not campaigns)