feat(dgw): make agent tunnel always available

README.md

@@ -278,6 +278,11 @@ Stable options are:
 
     See the [Cookbook](./docs/COOKBOOK.md) for configuration examples.
 
+- **AgentTunnel** (_Object_): QUIC-based agent tunnel configuration.
+    Gateway always starts the listener and fails startup if it cannot initialize or bind.
+
+    * **ListenPort** (_Integer_): UDP port for the QUIC listener (default is `4433`).
+
 - **VerbosityProfile** (_String_): Logging verbosity profile (pre-defined tracing directives).
 
     Possible values:

config_schema.json

@@ -108,6 +108,10 @@
       "$ref": "#/definitions/ProxyConf",
       "description": "HTTP/SOCKS proxy configuration for outbound requests."
     },
+    "AgentTunnel": {
+      "$ref": "#/definitions/AgentTunnelConf",
+      "description": "QUIC-based agent tunnel configuration."
+    },
     "LogFile": {
       "type": "string",
       "description": "Path to the log file."
@@ -508,6 +512,19 @@
       },
       "additionalProperties": false
     },
+    "AgentTunnelConf": {
+      "type": "object",
+      "properties": {
+        "ListenPort": {
+          "type": "integer",
+          "minimum": 1,
+          "maximum": 65535,
+          "default": 4433,
+          "description": "UDP port for the QUIC listener."
+        }
+      },
+      "additionalProperties": false
+    },
     "DebugConf": {
       "type": "object",
       "properties": {