fix: prevent Traefik restart loops and improve Docker registry login

Registry Login Fixes:
- Filter out service names (minio, redis) from registry URL extraction
- Only recognize actual registry URLs (with TLD or port)
- Preserve port numbers in registry URLs (e.g. git.michaelschiemer.de:5000)
- Better error messages for failed logins

Traefik Restart Loop Prevention:
- Set traefik_auto_restart default to false in traefik role
- Add traefik_auto_restart, traefik_ssl_restart, gitea_auto_restart to staging vars
- Add guard to fix-gitea-traefik-connection.yml restart task
- Add guard and deprecation warning to update-gitea-traefik-service.yml

This ensures that:
- CI/CD pipelines won't cause Traefik restart loops
- Staging environment uses same safe defaults as production
- Deprecated playbooks fail by default unless explicitly enabled
- Only actual Docker registries are used for login, not service names

deployment/ansible/inventory/group_vars/staging/vars.yml

@@ -0,0 +1,113 @@
+---
+# Staging Deployment - Centralized Variables
+# These variables are used across all staging playbooks
+
+# System Maintenance
+system_update_packages: true
+system_apt_upgrade: dist
+system_enable_unattended_upgrades: true
+system_enable_unattended_reboot: false
+system_unattended_reboot_time: "02:00"
+system_enable_unattended_timer: true
+system_enable_docker_prune: false
+
+# Deployment Paths
+deploy_user_home: "/home/deploy"
+stacks_base_path: "/home/deploy/deployment/stacks"
+staging_stack_path: "{{ stacks_base_path }}/staging"
+postgresql_staging_stack_path: "{{ stacks_base_path }}/postgresql-staging"
+backups_path: "{{ deploy_user_home }}/deployment/backups"
+
+# Docker Registry
+docker_registry: "localhost:5000"
+docker_registry_url: "localhost:5000"
+docker_registry_external: "registry.michaelschiemer.de"
+docker_registry_username_default: "admin"
+# docker_registry_password_default should be set in vault as vault_docker_registry_password
+# If not using vault, override via -e docker_registry_password_default="your-password"
+docker_registry_password_default: ""
+registry_auth_path: "{{ stacks_base_path }}/registry/auth"
+
+# Application Configuration
+app_name: "framework"
+app_domain: "staging.michaelschiemer.de"
+staging_domain: "{{ app_domain }}"
+app_image: "{{ docker_registry }}/{{ app_name }}"
+app_image_external: "{{ docker_registry_external }}/{{ app_name }}"
+
+# Domain Configuration
+gitea_domain: "git.michaelschiemer.de"
+
+# Email Configuration
+mail_from_address: "noreply@{{ app_domain }}"
+acme_email: "kontakt@michaelschiemer.de"
+
+# SSL Certificate Domains
+ssl_domains:
+  - "{{ gitea_domain }}"
+  - "{{ app_domain }}"
+  - "michaelschiemer.de"
+
+# Health Check Configuration
+health_check_url: "https://{{ app_domain }}/health"
+health_check_retries: 10
+health_check_delay: 10
+
+# Rollback Configuration
+max_rollback_versions: 3
+rollback_timeout: 300
+
+# Wait Timeouts
+wait_timeout: 60
+
+# Git Configuration (for sync-code.yml)
+git_repository_url_default: "https://{{ gitea_domain }}/michael/michaelschiemer.git"
+git_branch_default: "staging"
+git_token: "{{ vault_git_token | default('') }}"
+git_username: "{{ vault_git_username | default('') }}"
+git_password: "{{ vault_git_password | default('') }}"
+
+# Database Configuration
+db_user_default: "postgres"
+db_name_default: "michaelschiemer_staging"
+db_host_default: "postgres-staging"
+
+# MinIO Object Storage Configuration
+minio_root_user: "{{ vault_minio_root_user | default('minioadmin') }}"
+minio_root_password: "{{ vault_minio_root_password | default('') }}"
+minio_api_domain: "minio-api.michaelschiemer.de"
+minio_console_domain: "minio.michaelschiemer.de"
+
+# WireGuard Configuration
+wireguard_interface: "wg0"
+wireguard_config_path: "/etc/wireguard"
+wireguard_port_default: 51820
+wireguard_network_default: "10.8.0.0/24"
+wireguard_server_ip_default: "10.8.0.1"
+wireguard_enable_ip_forwarding: true
+wireguard_config_file: "{{ wireguard_config_path }}/{{ wireguard_interface }}.conf"
+wireguard_private_key_file: "{{ wireguard_config_path }}/{{ wireguard_interface }}_private.key"
+wireguard_public_key_file: "{{ wireguard_config_path }}/{{ wireguard_interface }}_public.key"
+wireguard_client_configs_path: "{{ wireguard_config_path }}/clients"
+
+# WireGuard DNS Configuration
+# DNS server for VPN clients (points to VPN server IP)
+# This ensures internal services are resolved to VPN IPs
+wireguard_dns_servers:
+  - "{{ wireguard_server_ip_default }}"
+
+# Traefik Configuration
+# Disable automatic restarts after config deployment to prevent restart loops
+# Set to true only when explicitly needed (e.g., after major config changes)
+traefik_auto_restart: false
+
+# Traefik SSL Configuration
+# Disable automatic restarts during SSL certificate setup to prevent restart loops
+traefik_ssl_restart: false
+
+# Gitea Auto-Restart Configuration
+# Set to false to prevent automatic restarts when healthcheck fails
+# This prevents restart loops when Gitea is temporarily unavailable (e.g., during Traefik restarts)
+# Set to true only when explicitly needed for remediation
+gitea_auto_restart: false
+