Add configurable membership plans (free/plus/pro) synced to DB on boot, a
subscription guard middleware that blocks tenant endpoints on expired or
missing plans, and a MembershipBlockedView that surfaces the reason so
the admin can contact the tenant owner. Quota and brand-library reads now
honor the active plan's policy JSON and expired subscriptions.
- Implemented image folder repository with CRUD operations.
- Added image reference repository for managing image references to articles.
- Created image repository for handling image assets, including listing, inserting, updating, and deleting images.
- Introduced image usage repository to track storage usage and quotas for tenants.
- Added SQL queries for image assets, folders, references, and usage.
- Developed image handler for HTTP endpoints to manage images and folders.
- Created database migration scripts for image-related tables and structures.