[self-hosted] add netbird server (#5232)

* Unified NetBird combined server (Management, Signal, Relay, STUN) as a single executable with richer YAML configuration, validation, and defaults.
  * Official Dockerfile/image for single-container deployment.
  * Optional in-process profiling endpoint for diagnostics.
  * Multiplexing to route HTTP/gRPC/WebSocket traffic via one port; runtime hooks to inject custom handlers.
* **Chores**
  * Updated deployment scripts, compose files, and reverse-proxy templates to target the combined server; added example configs and getting-started updates.

combined/config-simple.yaml.example

@@ -0,0 +1,111 @@
+# NetBird Combined Server Configuration
+# Copy this file to config.yaml and customize for your deployment
+#
+# This is a Management server with optional embedded Signal, Relay, and STUN services.
+# By default, all services run locally. You can use external services instead by
+# setting the corresponding override fields.
+#
+# Architecture:
+#   - Management: Always runs locally (this IS the management server)
+#   - Signal: Local by default; set 'signalUri' to use external (disables local)
+#   - Relay: Local by default; set 'relays' to use external (disables local)
+#   - STUN: Local on port 3478 by default; set 'stuns' to use external instead
+
+server:
+  # Main HTTP/gRPC port for all services (Management, Signal, Relay)
+  listenAddress: ":443"
+
+  # Public address that peers will use to connect to this server
+  # Used for relay connections and management DNS domain
+  # Format: protocol://hostname:port (e.g., https://server.mycompany.com:443)
+  exposedAddress: "https://server.mycompany.com:443"
+
+  # STUN server ports (defaults to [3478] if not specified; set 'stuns' to use external)
+  # stunPorts:
+  #   - 3478
+
+  # Metrics endpoint port
+  metricsPort: 9090
+
+  # Healthcheck endpoint address
+  healthcheckAddress: ":9000"
+
+  # Logging configuration
+  logLevel: "info"    # Default log level for all components: panic, fatal, error, warn, info, debug, trace
+  logFile: "console"  # "console" or path to log file
+
+  # TLS configuration (optional)
+  tls:
+    certFile: ""
+    keyFile: ""
+    letsencrypt:
+      enabled: false
+      dataDir: ""
+      domains: []
+      email: ""
+      awsRoute53: false
+
+  # Shared secret for relay authentication (required when running local relay)
+  authSecret: "your-secret-key-here"
+
+  # Data directory for all services
+  dataDir: "/var/lib/netbird/"
+
+  # ============================================================================
+  # External Service Overrides (optional)
+  # Use these to point to external Signal, Relay, or STUN servers instead of
+  # running them locally. When set, the corresponding local service is disabled.
+  # ============================================================================
+
+  # External STUN servers - disables local STUN server
+  # stuns:
+  #   - uri: "stun:stun.example.com:3478"
+  #   - uri: "stun:stun.example.com:3479"
+
+  # External relay servers - disables local relay server
+  # relays:
+  #   addresses:
+  #     - "rels://relay.example.com:443"
+  #   credentialsTTL: "12h"
+  #   secret: "relay-shared-secret"
+
+  # External signal server - disables local signal server
+  # signalUri: "https://signal.example.com:443"
+
+  # ============================================================================
+  # Management Settings
+  # ============================================================================
+
+  # Metrics and updates
+  disableAnonymousMetrics: false
+  disableGeoliteUpdate: false
+
+  # Embedded authentication/identity provider (Dex) configuration (always enabled)
+  auth:
+    # OIDC issuer URL - must be publicly accessible
+    issuer: "https://server.mycompany.com/oauth2"
+    localAuthDisabled: false
+    signKeyRefreshEnabled: false
+    # OAuth2 redirect URIs for dashboard
+    dashboardRedirectURIs:
+      - "https://app.netbird.io/nb-auth"
+      - "https://app.netbird.io/nb-silent-auth"
+    # OAuth2 redirect URIs for CLI
+    cliRedirectURIs:
+      - "http://localhost:53000/"
+    # Optional initial admin user
+    # owner:
+    #   email: "admin@example.com"
+    #   password: "initial-password"
+
+  # Store configuration
+  store:
+    engine: "sqlite"  # sqlite, postgres, or mysql
+    dsn: ""  # Connection string for postgres or mysql
+    encryptionKey: ""
+
+  # Reverse proxy settings (optional)
+  # reverseProxy:
+  #   trustedHTTPProxies: []
+  #   trustedHTTPProxiesCount: 0
+  #   trustedPeers: []