feat(sidechats): headless gateway new channel auto-provisioning and dedicated heartbeat channel

bin/dm.py

@@ -598,6 +598,60 @@ def dm_send(agent, target, message, verify=True, raw=False,
         except Exception as _e:
             log_event({"type": "gateway_fallback", "id": msg_id, "error": str(_e)[:100]})
 
+    # Fast gateway auto-provisioning for named sidechat targets:
+    if not is_uuid and recipient in VALID_AGENTS and target != "main":
+        try:
+            import muse_hybrid
+            matched_uuid = None
+            gw_threads, gw_t_err = muse_hybrid.get_threads(recipient)
+            if not gw_t_err and gw_threads:
+                for t in gw_threads:
+                    t_title = (t.get("title") or "").strip().lower()
+                    if t_title == target.strip().lower():
+                        matched_uuid = t.get("session_id")
+                        break
+
+            if not matched_uuid:
+                # Spawn a brand new sidechat channel via fast headless gateway
+                res, err = muse_hybrid.start_session(recipient, title=target)
+                if res and not err and res.get("session_id"):
+                    matched_uuid = res.get("session_id")
+                    log_event({"type": "sidechat_autoprovisioned", "id": msg_id, "target": target,
+                               "thread_uuid": matched_uuid, "agent": recipient, "transport": "gateway"})
+
+            if matched_uuid:
+                # Save mapping to job-sidechats.json
+                sc_data = load_sidechat_map()
+                save_key = f"{target}@{recipient}" if f"{target}@{recipient}" in sc_data else target
+                sc_data[save_key] = {
+                    "thread_uuid": matched_uuid,
+                    "agent": recipient,
+                    "title": target,
+                    "created_at": datetime.now(timezone.utc).isoformat()
+                }
+                tmp_sc = f"{SIDCHAT_MAP_FILE}.tmp.{os.getpid()}"
+                with open(tmp_sc, "w", encoding="utf-8") as f:
+                    json.dump(sc_data, f, indent=2)
+                os.replace(tmp_sc, SIDCHAT_MAP_FILE)
+
+                # Send immediately via gateway
+                gw_res, gw_err = muse_hybrid.send_message(recipient, tagged, thread_id=matched_uuid, wait=0)
+                if gw_res and not gw_err:
+                    thread_uuid = matched_uuid
+                    tags["thread"] = thread_uuid
+                    log_event({"type": "verified", "id": msg_id, "agent": agent, "to": recipient,
+                               "target": target, "thread_uuid": thread_uuid, "transport": "gateway",
+                               "placement": "confirmed"})
+                    log_event({"type": "send_done", "id": msg_id, "agent": agent, "to": recipient, "target": target})
+                    log_event({"type": "sent", "id": msg_id, "agent": agent, "to": recipient, "target": target,
+                               "verified": True, "transport": "gateway", "tags": tags})
+                    print(f"DM {msg_id} from {agent} to {recipient}/{target}: SENT and VERIFIED thread={thread_uuid} (gateway, auto-provisioned)")
+                    if tags.get("reply:expected"):
+                        _register_followup(msg_id, agent, recipient, target, tags)
+                    return msg_id
+        except Exception as _ge:
+            log_event({"type": "gateway_autoprovision_fallback", "id": msg_id, "error": str(_ge)[:100]})
+
     if target == "main":
         _rc, _out, _err = run_full(f"{NETVM_EXEC} {recipient} -- python3 {API} --account {recipient} sidechat main")
     else: