feat: bundle and sync official Hysteria2 install script locally

Store install_server.sh in role files, compare SHA256 with get.hy2.sh on the control node before install/update, refresh the bundled copy when upstream changes, then copy and run it on VPS.

roles/hysteria2/defaults/main.yml

@@ -26,6 +26,12 @@ hysteria2_configure_firewall: true
 hysteria2_config_path: /etc/hysteria/config.yaml
 hysteria2_service_name: hysteria-server
 
+# Официальный install_server.sh: хранится в roles/hysteria2/files/, синхронизируется с get.hy2.sh
+hysteria2_install_script_url: "https://get.hy2.sh/"
+hysteria2_install_script_name: install_server.sh
+hysteria2_install_script_staging_dir: "{{ playbook_dir }}/.cache/hysteria2"
+hysteria2_install_script_remote_path: /tmp/hysteria2-install_server.sh
+
 hysteria2_output_dir: "{{ playbook_dir }}/output"
 hysteria2_output_name: "{{ inventory_hostname }}"