refactor(external_cmd_selector): rework parameters (#8198)

* refactor(external_cmd_selector): rework parameters

Signed-off-by: Batuhan Beytekin <batuhanbeytekin@gmail.com>

* style(pre-commit): autofix

---------

Signed-off-by: Batuhan Beytekin <batuhanbeytekin@gmail.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

Author: batuhanbeytekin

Diff for: control/autoware_external_cmd_selector/README.md

@@ -32,3 +32,7 @@ The current mode is set via service, `remote` is remotely operated, `local` is t
 | `/external/selected/hazard_lights_cmd`                 | autoware_vehicle_msgs::msg::HazardLightsCommand   | Pass through hazard light with current mode.    |
 | `/external/selected/heartbeat`                         | TBD                                               | Pass through heartbeat with current mode.       |
 | `/external/selected/turn_indicators_cmd`               | autoware_vehicle_msgs::msg::TurnIndicatorsCommand | Pass through turn indicator with current mode.  |
+
+## Parameters
+
+{{json_to_markdown("control/autoware_external_cmd_selector/schema/external_cmd_selector.schema.json")}}

Diff for: control/autoware_external_cmd_selector/schema/external_cmd_selector.schema.json

@@ -0,0 +1,36 @@
+{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+  "title": "Parameters for external_cmd_selector",
+  "type": "object",
+  "definitions": {
+    "external_cmd_selector_node": {
+      "type": "object",
+      "properties": {
+        "update_rate": {
+          "type": "number",
+          "default": 10.0,
+          "description": "The rate in Hz at which the external command selector node updates."
+        },
+        "initial_selector_mode": {
+          "type": "string",
+          "enum": ["local", "remote"],
+          "default": "local",
+          "description": "The initial mode for command selection, either 'local' or 'remote'."
+        }
+      },
+      "required": ["update_rate", "initial_selector_mode"]
+    }
+  },
+  "properties": {
+    "/**": {
+      "type": "object",
+      "properties": {
+        "ros__parameters": {
+          "$ref": "#/definitions/external_cmd_selector_node"
+        }
+      },
+      "required": ["ros__parameters"]
+    }
+  },
+  "required": ["/**"]
+}