feat(rathole): add CloudronManifest.json and start.sh

- Implements CloudronManifest.json with port and environment variables
- Adds start.sh to generate rathole.toml and start the server

🤖 Generated with Gemini CLI
Co-Authored-By: Gemini <noreply@google.com>

CloudronPackages/Rathole/start.sh

@@ -0,0 +1,16 @@
+#!/bin/bash
+
+set -euo pipefail
+
+# Set default port if not provided
+: ${RATHOLE_SERVER_PORT:=2333}
+
+# Generate rathole.toml configuration file
+cat <<EOF > /app/data/rathole.toml
+[server]
+bind_addr = "0.0.0.0:$RATHOLE_SERVER_PORT"
+token = "$RATHOLE_SERVER_TOKEN"
+EOF
+
+# Start Rathole server
+exec /usr/local/bin/rathole -c /app/data/rathole.toml