feat(hub): raise agent turns/time limits and notify teachers on failure

Defaults and silo env go to 150 turns / 1800s wall clock. Run completion
appends a clear Feishu notice for max-turns, timeout, and other failures
(partial answer kept). Startup process-restart kills notify the bound chat.
Release v0.0.38.

hub/package-lock.json

@@ -1,12 +1,12 @@
 {
   "name": "@paradigm/hub",
-  "version": "0.0.37",
+  "version": "0.0.38",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "@paradigm/hub",
-      "version": "0.0.37",
+      "version": "0.0.38",
       "dependencies": {
         "@alicloud/credentials": "^2.4.5",
         "@alicloud/docmind-api20220711": "^1.4.15",