docs: update architecture — 47 tools, user file library, teams, branding, runtime settings

apps/docs/guide/architecture.md

@@ -46,13 +46,16 @@ Shared TypeScript types, constants (like `APP_VERSION` and tool definitions), an
 
 ### API (`apps/api`)
 
-A Fastify v5 server that handles:
+A Fastify v5 server exposing 47 tool routes (34 standard image operations + 13 AI-powered) that handles:
 - File uploads, temporary workspace management, and persistent file storage
+- User file library with version chains (`user_files` table) -- each processed result links back to its source file and records which tool was applied, with auto-generated thumbnails for the Files page
 - Tool execution (routes each tool request to the image engine or AI bridge)
 - Pipeline orchestration (chaining multiple tools sequentially)
 - Batch processing with concurrency control via p-queue
-- User authentication, teams, API key management, and rate limiting
-- Admin settings (tool visibility, feature flags, cleanup config, branding)
+- User authentication, RBAC (admin/user roles with a full permission set), API key management, and rate limiting
+- Teams management -- admin-only CRUD; users are assigned to a team via the `team` field on their profile
+- Runtime settings -- a key-value store in the `settings` table that controls `disabledTools`, `enableExperimentalTools`, `loginAttemptLimit`, and other operational knobs without redeploying
+- Custom branding -- logo upload endpoint; the uploaded image is stored at `data/branding/logo.png` and served to the frontend
 - Swagger/OpenAPI documentation at `/api/docs`
 - Serving the built frontend as a SPA in production