feat: add permission profile list api (#23412)

## Why

Clients need a typed permission-profile catalog instead of
reconstructing that state from config internals.

## What changed

- Added `permissionProfile/list` to the app-server v2 protocol with
cursor pagination and optional `cwd`.
- The list response includes built-in permission profiles plus
config-defined `[permissions.<id>]` profiles from the effective config
for the request context.
- Permission profiles keep optional `description` metadata for display
purposes.
- App-server docs and schema fixtures are updated for the new RPC.

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

@@ -1429,6 +1429,30 @@
           "title": "ExperimentalFeature/listRequest",
           "type": "object"
         },
+        {
+          "properties": {
+            "id": {
+              "$ref": "#/definitions/v2/RequestId"
+            },
+            "method": {
+              "enum": [
+                "permissionProfile/list"
+              ],
+              "title": "PermissionProfile/listRequestMethod",
+              "type": "string"
+            },
+            "params": {
+              "$ref": "#/definitions/v2/PermissionProfileListParams"
+            }
+          },
+          "required": [
+            "id",
+            "method",
+            "params"
+          ],
+          "title": "PermissionProfile/listRequest",
+          "type": "object"
+        },
         {
           "properties": {
             "id": {
@@ -11708,6 +11732,78 @@
           }
         ]
       },
+      "PermissionProfileListParams": {
+        "$schema": "http://json-schema.org/draft-07/schema#",
+        "properties": {
+          "cursor": {
+            "description": "Opaque pagination cursor returned by a previous call.",
+            "type": [
+              "string",
+              "null"
+            ]
+          },
+          "cwd": {
+            "description": "Optional working directory to resolve project config layers.",
+            "type": [
+              "string",
+              "null"
+            ]
+          },
+          "limit": {
+            "description": "Optional page size; defaults to the full result set.",
+            "format": "uint32",
+            "minimum": 0.0,
+            "type": [
+              "integer",
+              "null"
+            ]
+          }
+        },
+        "title": "PermissionProfileListParams",
+        "type": "object"
+      },
+      "PermissionProfileListResponse": {
+        "$schema": "http://json-schema.org/draft-07/schema#",
+        "properties": {
+          "data": {
+            "items": {
+              "$ref": "#/definitions/v2/PermissionProfileSummary"
+            },
+            "type": "array"
+          },
+          "nextCursor": {
+            "description": "Opaque cursor to pass to the next call to continue after the last item. If None, there are no more items to return.",
+            "type": [
+              "string",
+              "null"
+            ]
+          }
+        },
+        "required": [
+          "data"
+        ],
+        "title": "PermissionProfileListResponse",
+        "type": "object"
+      },
+      "PermissionProfileSummary": {
+        "properties": {
+          "description": {
+            "description": "Optional user-facing description for display in clients.",
+            "type": [
+              "string",
+              "null"
+            ]
+          },
+          "id": {
+            "description": "Available permission profile identifier.",
+            "type": "string"
+          }
+        },
+        "required": [
+          "id"
+        ],
+        "type": "object"
+      },
       "Personality": {
         "enum": [
           "none",