Unable to determine a valid web application host for Azure authentication.
Resolution order: request host (`X-Forwarded-Host`, `X-Original-Host`, then request URL), environment variable `WEB_CONFIG_BASE_URL`, then app setting `BaseUrl`.
Allowed host patterns: *.azurewebsites.net, *.paykonnect.dev, *.paykonnect.com.
Troubleshooting: verify the active host is expected, verify `WEB_CONFIG_BASE_URL` on the active App Service slot, verify `BaseUrl` in the active Azure auth config, and update `AllowedWebAppHostPatterns` if a new domain should be allowed.