refactor(web): implement nginx reverse proxy for telemetry dashboard

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

.github/workflows/deploy.yml

@@ -77,7 +77,6 @@ jobs:
           labels: ${{ steps.meta.outputs.labels }}
           build-args: |
             VITE_API_BASE_URL=${{ env.VITE_API_BASE_URL }}
-            VITE_TELEMETRY_URL=${{ vars.VITE_TELEMETRY_URL || 'https://telemetry.zeavisedu.asepharyana.my.id' }}
           cache-from: type=gha,scope=${{ matrix.service.name }}
           cache-to: type=gha,mode=max,scope=${{ matrix.service.name }}