feat(feedback): Add content improvement feedback system

Frontend (frontend/app.js):

- Add textarea for improvement feedback

- Add submit button with loading state

- Handle API response and display improved content

Backend (backend/copywriter.py):

- Add improve_copy() method using Cohere API

- Integrate retry mechanism for API calls

Backend (backend/main.py):

- Add /improve-content POST endpoint

- Implement error handling and return improved content with metadata

Testing:

- Verified feedback submission flow

- Confirmed improved content generation

- Tested error scenarios and loading states

.gitignore

@@ -38,6 +38,11 @@ data/past_campaigns/*
 data/user_queries/*
 !data/past_campaigns/.gitkeep
 !data/user_queries/.gitkeep
+backend/data/vector_store/*
+!backend/data/vector_store/.gitkeep
+
+# Logs
+logs/*
 
 # OS specific
 .DS_Store