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/features/background-agent/manager.ts

@@ -272,6 +272,7 @@ export class BackgroundManager {
       body: {
         parentID: input.parentSessionID,
         title: `${input.description} (@${input.agent} subagent)`,
+        ...(input.sessionPermission ? { permission: input.sessionPermission } : {}),
       } as Record<string, unknown>,
       query: {
         directory: parentDirectory,