Aggiunge registry nodi stream e provisioning Hetzner/lab per lo scale-out.

Prepara l'architettura multi-nodo (MediaMTX+ffmpeg) con assignment URL per sessione, admin di provision/drain e provider Cloud/DNS astratti verso mltv-stream.net.

Co-authored-by: Cursor <cursoragent@cursor.com>

infra/stream-node/cloud-init.yaml

@@ -0,0 +1,41 @@
+#cloud-config
+# Cloud-init minimale per nodo stream Hetzner (MediaMTX + ffmpeg).
+# Uso in .env produzione:
+#   HCLOUD_USER_DATA_FILE=/opt/matchlivetv/infra/stream-node/cloud-init.yaml
+#
+# Per boot più veloci: creare uno snapshot dopo il primo setup e usare HCLOUD_IMAGE=<snapshot>.
+
+package_update: true
+packages:
+  - docker.io
+  - ffmpeg
+  - curl
+runcmd:
+  - systemctl enable --now docker
+  - mkdir -p /opt/stream-node /recordings /slates
+  - |
+    cat >/opt/stream-node/docker-compose.yml <<'EOF'
+    services:
+      mediamtx:
+        image: bluenviron/mediamtx:latest
+        network_mode: host
+        restart: unless-stopped
+        volumes:
+          - ./mediamtx.yml:/mediamtx.yml:ro
+          - /recordings:/recordings
+          - /slates:/slates:ro
+        command: /mediamtx.yml
+    EOF
+  - |
+    cat >/opt/stream-node/mediamtx.yml <<'EOF'
+    logLevel: info
+    api: yes
+    apiAddress: :9997
+    rtmp: yes
+    rtmpAddress: :1935
+    hls: yes
+    hlsAddress: :8888
+    paths:
+      all_others:
+    EOF
+  - cd /opt/stream-node && docker compose up -d