Add agentic tool access for Neuron in DHARMA rooms

Adds handle_dharma_room_turn_agentic to chat.el — same full tool loop
as handle_chat_agentic but reads transcript directly (not message), and
returns {response, cgi_id, tools_used} to match the dharma room shape.

Registers dharma_room_turn_agentic as a new event type in routes.el so
the studio can dispatch @neuron turns through this dedicated path.

dist/routes.c

@@ -39,6 +39,7 @@ el_val_t dispatch_tool(el_val_t tool_name, el_val_t tool_input);
 el_val_t handle_chat_agentic(el_val_t body);
 el_val_t handle_chat_as_soul(el_val_t body);
 el_val_t handle_dharma_room_turn(el_val_t body);
+el_val_t handle_dharma_room_turn_agentic(el_val_t body);
 el_val_t auto_persist(el_val_t req, el_val_t resp);
 el_val_t auth_headers(el_val_t tok);
 el_val_t axon_get(el_val_t path);
@@ -186,6 +187,9 @@ el_val_t handle_dharma_recv(el_val_t body) {
   if (str_eq(eff_event, EL_STR("health"))) {
     return route_health();
   }
+  if (str_eq(eff_event, EL_STR("dharma_room_turn_agentic"))) {
+    return handle_dharma_room_turn_agentic(eff_payload);
+  }
   if (str_eq(eff_event, EL_STR("dharma_room_turn"))) {
     return handle_dharma_room_turn(eff_payload);
   }