Add request permissions tool (#13092)

Adds a built-in `request_permissions` tool and wires it through the
Codex core, protocol, and app-server layers so a running turn can ask
the client for additional permissions instead of relying on a static
session policy.

The new flow emits a `RequestPermissions` event from core, tracks the
pending request by call ID, forwards it through app-server v2 as an
`item/permissions/requestApproval` request, and resumes the tool call
once the client returns an approved subset of the requested permission
profile.

codex-rs/app-server-protocol/schema/json/PermissionsRequestApprovalResponse.json

@@ -0,0 +1,160 @@
+{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+  "definitions": {
+    "AbsolutePathBuf": {
+      "description": "A path that is guaranteed to be absolute and normalized (though it is not guaranteed to be canonicalized or exist on the filesystem).\n\nIMPORTANT: When deserializing an `AbsolutePathBuf`, a base path must be set using [AbsolutePathBufGuard::new]. If no base path is set, the deserialization will fail unless the path being deserialized is already absolute.",
+      "type": "string"
+    },
+    "AdditionalFileSystemPermissions": {
+      "properties": {
+        "read": {
+          "items": {
+            "$ref": "#/definitions/AbsolutePathBuf"
+          },
+          "type": [
+            "array",
+            "null"
+          ]
+        },
+        "write": {
+          "items": {
+            "$ref": "#/definitions/AbsolutePathBuf"
+          },
+          "type": [
+            "array",
+            "null"
+          ]
+        }
+      },
+      "type": "object"
+    },
+    "AdditionalNetworkPermissions": {
+      "properties": {
+        "enabled": {
+          "type": [
+            "boolean",
+            "null"
+          ]
+        }
+      },
+      "type": "object"
+    },
+    "GrantedMacOsPermissions": {
+      "properties": {
+        "accessibility": {
+          "type": [
+            "boolean",
+            "null"
+          ]
+        },
+        "automations": {
+          "anyOf": [
+            {
+              "$ref": "#/definitions/MacOsAutomationPermission"
+            },
+            {
+              "type": "null"
+            }
+          ]
+        },
+        "calendar": {
+          "type": [
+            "boolean",
+            "null"
+          ]
+        },
+        "preferences": {
+          "anyOf": [
+            {
+              "$ref": "#/definitions/MacOsPreferencesPermission"
+            },
+            {
+              "type": "null"
+            }
+          ]
+        }
+      },
+      "type": "object"
+    },
+    "GrantedPermissionProfile": {
+      "properties": {
+        "fileSystem": {
+          "anyOf": [
+            {
+              "$ref": "#/definitions/AdditionalFileSystemPermissions"
+            },
+            {
+              "type": "null"
+            }
+          ]
+        },
+        "macos": {
+          "anyOf": [
+            {
+              "$ref": "#/definitions/GrantedMacOsPermissions"
+            },
+            {
+              "type": "null"
+            }
+          ]
+        },
+        "network": {
+          "anyOf": [
+            {
+              "$ref": "#/definitions/AdditionalNetworkPermissions"
+            },
+            {
+              "type": "null"
+            }
+          ]
+        }
+      },
+      "type": "object"
+    },
+    "MacOsAutomationPermission": {
+      "oneOf": [
+        {
+          "enum": [
+            "none",
+            "all"
+          ],
+          "type": "string"
+        },
+        {
+          "additionalProperties": false,
+          "properties": {
+            "bundle_ids": {
+              "items": {
+                "type": "string"
+              },
+              "type": "array"
+            }
+          },
+          "required": [
+            "bundle_ids"
+          ],
+          "title": "BundleIdsMacOsAutomationPermission",
+          "type": "object"
+        }
+      ]
+    },
+    "MacOsPreferencesPermission": {
+      "enum": [
+        "none",
+        "read_only",
+        "read_write"
+      ],
+      "type": "string"
+    }
+  },
+  "properties": {
+    "permissions": {
+      "$ref": "#/definitions/GrantedPermissionProfile"
+    }
+  },
+  "required": [
+    "permissions"
+  ],
+  "title": "PermissionsRequestApprovalResponse",
+  "type": "object"
+}