support plugin/list. (#13540)

Introduce a plugin/list which reads from local marketplace.json.
Also update the signature for plugin/install.

codex-rs/app-server-protocol/schema/json/codex_app_server_protocol.v2.schemas.json

@@ -1211,6 +1211,30 @@
           "title": "Skills/listRequest",
           "type": "object"
         },
+        {
+          "properties": {
+            "id": {
+              "$ref": "#/definitions/RequestId"
+            },
+            "method": {
+              "enum": [
+                "plugin/list"
+              ],
+              "title": "Plugin/listRequestMethod",
+              "type": "string"
+            },
+            "params": {
+              "$ref": "#/definitions/PluginListParams"
+            }
+          },
+          "required": [
+            "id",
+            "method",
+            "params"
+          ],
+          "title": "Plugin/listRequest",
+          "type": "object"
+        },
         {
           "properties": {
             "id": {
@@ -8371,21 +8395,15 @@
     "PluginInstallParams": {
       "$schema": "http://json-schema.org/draft-07/schema#",
       "properties": {
-        "cwd": {
-          "type": [
-            "string",
-            "null"
-          ]
-        },
-        "marketplaceName": {
-          "type": "string"
+        "marketplacePath": {
+          "$ref": "#/definitions/AbsolutePathBuf"
         },
         "pluginName": {
           "type": "string"
         }
       },
       "required": [
-        "marketplaceName",
+        "marketplacePath",
         "pluginName"
       ],
       "title": "PluginInstallParams",
@@ -8396,6 +8414,104 @@
       "title": "PluginInstallResponse",
       "type": "object"
     },
+    "PluginListParams": {
+      "$schema": "http://json-schema.org/draft-07/schema#",
+      "properties": {
+        "cwds": {
+          "description": "Optional working directories used to discover repo marketplaces. When omitted, only home-scoped marketplaces are considered.",
+          "items": {
+            "$ref": "#/definitions/AbsolutePathBuf"
+          },
+          "type": [
+            "array",
+            "null"
+          ]
+        }
+      },
+      "title": "PluginListParams",
+      "type": "object"
+    },
+    "PluginListResponse": {
+      "$schema": "http://json-schema.org/draft-07/schema#",
+      "properties": {
+        "marketplaces": {
+          "items": {
+            "$ref": "#/definitions/PluginMarketplaceEntry"
+          },
+          "type": "array"
+        }
+      },
+      "required": [
+        "marketplaces"
+      ],
+      "title": "PluginListResponse",
+      "type": "object"
+    },
+    "PluginMarketplaceEntry": {
+      "properties": {
+        "name": {
+          "type": "string"
+        },
+        "path": {
+          "type": "string"
+        },
+        "plugins": {
+          "items": {
+            "$ref": "#/definitions/PluginSummary"
+          },
+          "type": "array"
+        }
+      },
+      "required": [
+        "name",
+        "path",
+        "plugins"
+      ],
+      "type": "object"
+    },
+    "PluginSource": {
+      "oneOf": [
+        {
+          "properties": {
+            "path": {
+              "type": "string"
+            },
+            "type": {
+              "enum": [
+                "local"
+              ],
+              "title": "LocalPluginSourceType",
+              "type": "string"
+            }
+          },
+          "required": [
+            "path",
+            "type"
+          ],
+          "title": "LocalPluginSource",
+          "type": "object"
+        }
+      ]
+    },
+    "PluginSummary": {
+      "properties": {
+        "enabled": {
+          "type": "boolean"
+        },
+        "name": {
+          "type": "string"
+        },
+        "source": {
+          "$ref": "#/definitions/PluginSource"
+        }
+      },
+      "required": [
+        "enabled",
+        "name",
+        "source"
+      ],
+      "type": "object"
+    },
     "ProductSurface": {
       "enum": [
         "chatgpt",