feat: adjusted UI api auth

[Mesh-ach]

changes

• Replaced OAuth2PasswordBearer with HTTPBearer for JWT-based auth
• Renamed auth scheme to clarify usage (Bearer token (from API key login)) in FastAPI docs
• Removed legacy username/password flow references

context

• FastAPI UI incorrectly showed OAuth2 login form due to OAuth2PasswordBearer, which we don’t use
• Backend relies solely on API keys to issue JWTs; username/password flow is deprecated

questions

No question at this time

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[emmaeturner]

This PR correctly removes OAuth2PasswordBearer and replaces it with HTTPBearer to align FastAPI's UI and backend behavior with the actual JWT-based, API-key issued authentication. Swagger docs now behave as expected. I’ve verified no username/password flows remain. Just one small suggestion: either fully remove the commented OAuth2 code or leave a TODO note for clarity. Once the type-check failure is resolved, this is good to go!

[Mesh-ach]

This PR correctly removes OAuth2PasswordBearer and replaces it with HTTPBearer to align FastAPI's UI and backend behavior with the actual JWT-based, API-key issued authentication. Swagger docs now behave as expected. I’ve verified no username/password flows remain. Just one small suggestion: either fully remove the commented OAuth2 code or leave a TODO note for clarity. Once the type-check failure is resolved, this is good to go!

Got it, will remove the comments now.