Revert "Merge branch 'rhan/approval-source' into rhan/escalations-approvals-sandbox"

This reverts commit 2ad79b06f0, reversing
changes made to 7a2c92bf89.

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

@@ -536,15 +536,6 @@
     "AppToolsConfig": {
       "type": "object"
     },
-    "ApprovalSourceMetadata": {
-      "enum": [
-        "guardian",
-        "user",
-        "policy",
-        "unknown"
-      ],
-      "type": "string"
-    },
     "ApprovalsReviewer": {
       "description": "Configures who approval requests are routed to for review. Examples include sandbox escapes, blocked network access, MCP approval prompts, and ARC escalations. Defaults to `user`. `guardian_subagent` uses a carefully prompted subagent to gather relevant context and apply a risk-based decision framework before approving or denying the request.",
       "enum": [
@@ -7524,16 +7515,6 @@
     },
     "ResponseItemMetadata": {
       "properties": {
-        "approval_source": {
-          "anyOf": [
-            {
-              "$ref": "#/definitions/ApprovalSourceMetadata"
-            },
-            {
-              "type": "null"
-            }
-          ]
-        },
         "is_tool_call_escalated": {
           "type": [
             "boolean",