app-server support for Windows sandbox setup. (#12025)

app-server support for initiating Windows sandbox setup.
server responds quickly to setup request and makes a future RPC call
back to client when the setup finishes.

The TUI implementation is unaffected but in a future PR I'll update the
TUI to use the shared setup helper
(`windows_sandbox.run_windows_sandbox_setup`)

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

@@ -1059,6 +1059,30 @@
           "title": "McpServerStatus/listRequest",
           "type": "object"
         },
+        {
+          "properties": {
+            "id": {
+              "$ref": "#/definitions/RequestId"
+            },
+            "method": {
+              "enum": [
+                "windowsSandbox/setupStart"
+              ],
+              "title": "WindowsSandbox/setupStartRequestMethod",
+              "type": "string"
+            },
+            "params": {
+              "$ref": "#/definitions/v2/WindowsSandboxSetupStartParams"
+            }
+          },
+          "required": [
+            "id",
+            "method",
+            "params"
+          ],
+          "title": "WindowsSandbox/setupStartRequest",
+          "type": "object"
+        },
         {
           "properties": {
             "id": {
@@ -8708,6 +8732,26 @@
           "title": "Windows/worldWritableWarningNotification",
           "type": "object"
         },
+        {
+          "properties": {
+            "method": {
+              "enum": [
+                "windowsSandbox/setupCompleted"
+              ],
+              "title": "WindowsSandbox/setupCompletedNotificationMethod",
+              "type": "string"
+            },
+            "params": {
+              "$ref": "#/definitions/v2/WindowsSandboxSetupCompletedNotification"
+            }
+          },
+          "required": [
+            "method",
+            "params"
+          ],
+          "title": "WindowsSandbox/setupCompletedNotification",
+          "type": "object"
+        },
         {
           "properties": {
             "method": {
@@ -17081,6 +17125,62 @@
         ],
         "type": "string"
       },
+      "WindowsSandboxSetupCompletedNotification": {
+        "$schema": "http://json-schema.org/draft-07/schema#",
+        "properties": {
+          "error": {
+            "type": [
+              "string",
+              "null"
+            ]
+          },
+          "mode": {
+            "$ref": "#/definitions/v2/WindowsSandboxSetupMode"
+          },
+          "success": {
+            "type": "boolean"
+          }
+        },
+        "required": [
+          "mode",
+          "success"
+        ],
+        "title": "WindowsSandboxSetupCompletedNotification",
+        "type": "object"
+      },
+      "WindowsSandboxSetupMode": {
+        "enum": [
+          "elevated",
+          "unelevated"
+        ],
+        "type": "string"
+      },
+      "WindowsSandboxSetupStartParams": {
+        "$schema": "http://json-schema.org/draft-07/schema#",
+        "properties": {
+          "mode": {
+            "$ref": "#/definitions/v2/WindowsSandboxSetupMode"
+          }
+        },
+        "required": [
+          "mode"
+        ],
+        "title": "WindowsSandboxSetupStartParams",
+        "type": "object"
+      },
+      "WindowsSandboxSetupStartResponse": {
+        "$schema": "http://json-schema.org/draft-07/schema#",
+        "properties": {
+          "started": {
+            "type": "boolean"
+          }
+        },
+        "required": [
+          "started"
+        ],
+        "title": "WindowsSandboxSetupStartResponse",
+        "type": "object"
+      },
       "WindowsWorldWritableWarningNotification": {
         "$schema": "http://json-schema.org/draft-07/schema#",
         "properties": {