Transition telemetry dashboard integration from an external URL approach to a local reverse proxy via Nginx. This simplifies client-side connectivity by routing all telemetry requests through the existing web server's domain.
- Configure Nginx to proxy `/telemetry/` sub-paths to the internal telemetry service
- Implement `sub_filter` in Nginx to rewrite root-relative paths for the SPA
- Remove `VITE_TELEMETRY_URL` build arguments and environment variable dependencies
- Simplify `TelemetryPage` to use a relative `/telemetry` base path
- Clean up deployment workflows and Dockerfile by removing unused telemetry build args
Replace the hardcoded Nginx proxy configuration with a dynamic environment variable approach. This allows the telemetry dashboard to be loaded via a public URL instead of relying on a local Tailscale proxy.
- Add `VITE_TELEMETRY_URL` build argument to Dockerfile
- Pass `VITE_TELEMETRY_URL` through GitHub Actions deployment workflow
- Remove `/telemetry/` location block from nginx.conf
- Update `TelemetryPage` to use the new environment variable and improve iframe loading state management