Fix scheduled tasks and improve task scheduling UX

- Fix Apple Container mount issue: move groups/CLAUDE.md to groups/global/
  directory (Apple Container only supports directory mounts, not file mounts)
- Fix scheduled tasks for main group: properly detect isMain based on
  group_folder instead of always setting false
- Add isScheduledTask flag so agent knows when running as scheduled task
- Improve schedule_task tool description with clear format examples for
  cron, interval, and once schedule types
- Update global CLAUDE.md with instructions for scheduled tasks to use
  mcp__nanoclaw__send_message when needed

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/container-runner.ts

@@ -26,6 +26,7 @@ export interface ContainerInput {
   groupFolder: string;
   chatJid: string;
   isMain: boolean;
+  isScheduledTask?: boolean;
 }
 
 export interface ContainerOutput {
@@ -68,12 +69,13 @@ function buildVolumeMounts(group: RegisteredGroup, isMain: boolean): VolumeMount
       readonly: false
     });
 
-    // Global CLAUDE.md (read-only for non-main)
-    const globalClaudeMd = path.join(GROUPS_DIR, 'CLAUDE.md');
-    if (fs.existsSync(globalClaudeMd)) {
+    // Global memory directory (read-only for non-main)
+    // Apple Container only supports directory mounts, not file mounts
+    const globalDir = path.join(GROUPS_DIR, 'global');
+    if (fs.existsSync(globalDir)) {
       mounts.push({
-        hostPath: globalClaudeMd,
-        containerPath: '/workspace/global/CLAUDE.md',
+        hostPath: globalDir,
+        containerPath: '/workspace/global',
         readonly: true
       });
     }