Fix frontend auth API base URL (Vercel)

[gitgrahamdunn]

Motivation

• The frontend was hardcoded to call a localhost backend which breaks when the backend is deployed to Vercel.
• Expose a Vite environment variable so the frontend can target the deployed backend (VITE_API_URL) while still falling back to same-origin for local single-server mode.

Description

• Centralized API base URL resolution in frontend/src/api.ts to read import.meta.env.VITE_API_URL and use window.location.origin as a fallback.
• Added a clear console.error when VITE_API_URL is not configured that instructs operators to set VITE_API_URL (example: https://gitplant-backend.vercel.app).
• Left request paths unchanged and ensured all API calls (including /auth/login) use the shared buildApiUrl helper so they target the configured base URL.
• Documented the env var in frontend/README.md and added frontend/.env.example with VITE_API_URL for local/dev setup.

Testing

• Built the frontend with npm --prefix frontend run build and the build completed successfully.
• Started the backend and dev frontend with VITE_API_URL=http://127.0.0.1:8000 and executed automated Playwright checks that clicked the Sign in button and observed a POST /auth/login request, confirming requests are routed via the configured base URL.
• One automated run showed a CORS/preflight failure when calling an API origin that was not properly reachable in that environment, which validates that requests are now routed to the intended origin (and demonstrates why the deployed backend must allow the frontend origin).
• How to test: set VITE_API_URL=https://gitplant-backend.vercel.app in the Vercel frontend project or in frontend/.env, run npm --prefix frontend run dev, open the app and click Sign in and verify a POST is sent to ${VITE_API_URL}/auth/login and successful login navigates to the dashboard; remove VITE_API_URL and refresh to confirm a clear console.error is emitted and the app falls back to same-origin.

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Codex Task

[vercel]

The latest updates on your projects. Learn more about Vercel for GitHub.

Project	Deployment	Actions	Updated (UTC)
gitplant	Ready	Preview, Comment	Feb 18, 2026 11:05pm
gitplant-backend	Ready	Preview, Comment	Feb 18, 2026 11:05pm
gitplant-oggy	Ready	Preview, Comment	Feb 18, 2026 11:05pm

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Preserve backward compatibility for API env variable

Reading only VITE_API_URL introduces a silent regression for existing deployments that still define VITE_API_BASE_URL (the previously documented key): after upgrading, configuredApiUrl becomes empty and the code falls back to window.location.origin, so auth/API calls are sent to the frontend origin and fail whenever frontend and backend are on different hosts. Please support both names during migration (e.g., prefer VITE_API_URL but fall back to VITE_API_BASE_URL) to avoid breaking current environments.

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