feat(platform): centralize api calls in nextjs for token handling (#10222)

This PR helps to send all the React query requests through a Next.js
server proxy. It works something like this: when a user sends a request,
our custom mutator sends a request to the proxy server, where we add the
auth token to the header and send it to the backend again. 🌐

Users can send a client-side request directly to the backend server
because their browser does have access to auth tokens, so they need to
go via the Next.js server. 🚀

### Changes 🏗️

- Change the position of the generated client, mutator, and transfer
inside `/src/app/api`
- Update the mutator to send the request to the proxy server 
- Add a proxy server at `/api/proxy`, which handles the request using
`makeAuthenticatedRequest` and `makeAuthenticatedFileUpload` helpers and
sends the request to the backend
- Remove `getSupabaseClient`, because we do not have access to the auth
token on client side, hence no need 🔑
- Update Orval configs to generate the client at the new position 
- Added new backend updates to the auto-generated client.

### Checklist 📋

#### For code changes:
- [x] I have clearly listed my changes in the PR description
- [x] I have made a test plan
- [x] I have tested my changes according to the test plan:
  - [x] The setting page is using React Query and is working fine.
  - [x] The mutator is sending requests to the proxy server correctly.
  - [x] The proxy server is handling requests correctly.
- [x] The response handling is correct in both the proxy server and the
custom mutator.

.gitignore

@@ -179,4 +179,4 @@ autogpt_platform/backend/settings.py
 .claude/settings.local.json
 
 # Auto generated client
-autogpt_platform/frontend/src/api/__generated__
+autogpt_platform/frontend/src/app/api/__generated__