Add session permission support to background agents for denying questions

Implements question-denied session permission rules when creating child
sessions via background task delegation. This prevents subagents from
asking questions by passing explicit permission configuration during
session creation.

🤖 GENERATED WITH ASSISTANCE OF OhMyOpenCode

src/tools/delegate-task/unstable-agent-permission.test.ts

@@ -0,0 +1,74 @@
+import { describe, expect, test } from "bun:test"
+
+import { executeUnstableAgentTask } from "./unstable-agent-task"
+
+describe("executeUnstableAgentTask session permission", () => {
+  test("passes question-deny session permission into background launch", async () => {
+    // given
+    const launchCalls: Array<Record<string, unknown>> = []
+    const mockManager = {
+      launch: async (input: Record<string, unknown>) => {
+        launchCalls.push(input)
+        return {
+          id: "bg_unstable_permission",
+          sessionID: "ses_unstable_permission",
+          description: "test task",
+          agent: "sisyphus-junior",
+          status: "running",
+        }
+      },
+      getTask: () => ({
+        id: "bg_unstable_permission",
+        sessionID: "ses_unstable_permission",
+        status: "interrupt",
+        description: "test task",
+        agent: "sisyphus-junior",
+        error: "stop after launch",
+      }),
+    }
+    const toolContext = {
+      sessionID: "parent-session",
+      messageID: "msg_parent",
+      agent: "sisyphus",
+      metadata: () => {},
+      abort: new AbortController().signal,
+    } satisfies Parameters<typeof executeUnstableAgentTask>[1]
+    const executorContext = {
+      manager: mockManager,
+      client: {
+        session: {
+          status: async () => ({ data: {} }),
+          messages: async () => ({ data: [] }),
+        },
+      },
+    } as unknown as Parameters<typeof executeUnstableAgentTask>[2]
+    const parentContext = {
+      sessionID: "parent-session",
+      messageID: "msg_parent",
+    } satisfies Parameters<typeof executeUnstableAgentTask>[3]
+
+    // when
+    await executeUnstableAgentTask(
+      {
+        prompt: "test prompt",
+        description: "test task",
+        category: "test",
+        load_skills: [],
+        run_in_background: false,
+      },
+      toolContext,
+      executorContext,
+      parentContext,
+      "sisyphus-junior",
+      undefined,
+      undefined,
+      "test-model",
+    )
+
+    // then
+    expect(launchCalls).toHaveLength(1)
+    expect(launchCalls[0]?.sessionPermission).toEqual([
+      { permission: "question", action: "deny", pattern: "*" },
+    ])
+  })
+})