feat: add plugin/read. (#14445)

return more information for a specific plugin.

codex-rs/app-server-protocol/schema/json/v2/PluginReadParams.json

@@ -0,0 +1,23 @@
+{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+  "definitions": {
+    "AbsolutePathBuf": {
+      "description": "A path that is guaranteed to be absolute and normalized (though it is not guaranteed to be canonicalized or exist on the filesystem).\n\nIMPORTANT: When deserializing an `AbsolutePathBuf`, a base path must be set using [AbsolutePathBufGuard::new]. If no base path is set, the deserialization will fail unless the path being deserialized is already absolute.",
+      "type": "string"
+    }
+  },
+  "properties": {
+    "marketplacePath": {
+      "$ref": "#/definitions/AbsolutePathBuf"
+    },
+    "pluginName": {
+      "type": "string"
+    }
+  },
+  "required": [
+    "marketplacePath",
+    "pluginName"
+  ],
+  "title": "PluginReadParams",
+  "type": "object"
+}