Add devigo deployment role for mini-vps production environment

- Created comprehensive devigo Ansible role with Podman Quadlet support
- Deployed devigo-site container (Hugo + nginx) via systemd
- Deployed devigo-decap-oauth OAuth2 proxy for Decap CMS
- Integrated with Caddy reverse proxy for HTTPS

Services deployed:
- devigo.no (apex domain, primary)
- www.devigo.no (redirects to apex)
- decap.jnss.me (OAuth proxy)

Key features:
- REGISTRY_AUTH_FILE environment for Podman GHCR authentication
- TRUSTED_ORIGINS (plural) for decapcms-oauth2 multi-origin support
- JavaScript-based Decap CMS initialization (eliminates YAML MIME dependency)
- nginx location block for YAML MIME type (text/yaml)
- Automated deployment via GitHub Actions CI/CD
- Comprehensive documentation with troubleshooting guide
- Architecture decision records

Fixes applied during deployment:
- OAuth origin trust validation (TRUSTED_ORIGINS vs TRUSTED_ORIGIN)
- MIME type handling strategy (location-specific vs server-level types block)
- Decap CMS initialization method (JavaScript vs link tag)
- Podman authentication for systemd services (REGISTRY_AUTH_FILE)

Testing status:
- ✅ MIME types verified (HTML, CSS, YAML all correct)
- ✅ OAuth authentication working
- ✅ Container image pulls from private GHCR
- ✅ Automated deployments functional
- ✅ Site fully operational at devigo.no

roles/devigo/templates/devigo-decap-oauth.container

@@ -0,0 +1,25 @@
+[Unit]
+Description=Decap CMS OAuth2 Proxy for Devigo
+After=network-online.target
+Wants=network-online.target
+
+[Container]
+Image={{ devigo_oauth_container_image }}
+ContainerName={{ devigo_oauth_container_name }}
+AutoUpdate=registry
+
+# Environment file with secrets
+EnvironmentFile={{ devigo_oauth_home }}/decap-oauth.env
+
+# Network
+PublishPort=127.0.0.1:{{ devigo_oauth_container_port }}:12000
+
+# Security
+NoNewPrivileges=true
+
+[Service]
+Restart=always
+TimeoutStartSec=900
+
+[Install]
+WantedBy=default.target