fix(athena): force athena-junior to background and exempt from hard TTL

Council sessions are long-running: athena-junior launches members then
waits for them via background_wait. Two changes prevent premature kills:

- Force run_in_background=true when subagent_type resolves to athena-junior,
  avoiding the 10-minute sync poll timeout (MAX_POLL_TIME_MS)
- Exempt athena-junior from the 30-minute TASK_TTL_MS hard cutoff since
  council members have their own independent TTLs
- Fix missing bulk_launch field in AthenaOverrideConfigSchema (type error)

src/tools/delegate-task/tools.ts

@@ -240,6 +240,17 @@ export function createDelegateTask(options: DelegateTaskToolOptions): ToolDefini
         fallbackChain = resolution.fallbackChain
       }
 
+      // Athena-junior council sessions are long-running (members do deep work).
+      // Force background to avoid the 10-minute sync poll timeout.
+      const isAthenaJunior = agentToUse.toLowerCase() === "athena-junior"
+      if (isAthenaJunior && !runInBackground) {
+        log("[task] Forcing athena-junior to background — council sessions exceed sync poll timeout", {
+          originalRunInBackground: args.run_in_background,
+          agentToUse,
+        })
+      }
+      const effectiveRunInBackground = runInBackground || isAthenaJunior
+
       const systemContent = buildSystemContent({
         skillContent,
         skillContents,
@@ -251,7 +262,7 @@ export function createDelegateTask(options: DelegateTaskToolOptions): ToolDefini
         availableSkills,
       })
 
-      if (runInBackground) {
+      if (effectiveRunInBackground) {
         return executeBackgroundTask(args, ctx, options, parentContext, agentToUse, categoryModel, systemContent, fallbackChain)
       }