Refactor AI proxy error handling and remove deprecated upload and event routes

- Updated `getAiProxy` function to return a JSON response for missing objects when the user is the owner.
- Removed the `upload.ts`, `event.ts`, and related middleware files to streamline the codebase.
- Cleaned up `handle-request.ts` and `index.ts` by removing unused imports and routes.
- Deleted chunk upload handling and related utility functions to simplify resource management.
- Enhanced app manager list functionality to support app creation if not found.

src/routes-simple/index.ts

@@ -1,6 +0,0 @@
-// import './code/upload.ts';
-import './event.ts';
-
-import './resources/upload.ts';
-import './resources/chunk.ts';
-// import './resources/get-resources.ts';