Migrate from GitHub to Gitea with CI/CD

- Add Gitea Actions workflow for automated frontend and API deployment
- Update all raw download URLs from GitHub to Gitea
- Remove deprecated Amplify config and GitHub-specific Terraform variables
- Clean up commented-out Amplify resources from Terraform
- Update documentation to reflect new repository and CI/CD setup

scripts/update-api-server.sh

@@ -1,6 +1,6 @@
 #!/bin/bash
 
-# Script to update API server via GitHub
+# Script to update API server via Gitea
 # Since we can't SSH directly, we'll use the API server to pull latest code
 
 echo "🚀 Updating API server with latest code..."