feat(chat): persona decides to buy/walk — auto-finish + tolerance (temper) + resume

The conversation now ENDS when the persona makes a decision (option C), not when the
trainee clicks a button:
- persona_id replies carry {reply, decision(none/buy/walk), mood}; when decision is
  buy/walk the session auto-finishes (won/lost) with a debrief that reveals latent
  details + per-turn 'turning points'.
- personas have a tolerance (1-5, 'temper'): impatient personas walk away fast after
  poor answers (fed via internal.misses on mood<=-1); tough 'wrong text' cases can
  still be won by a strong, gentle response (judge realism).
- trainee 'Finish' button removed; if they leave mid-chat an active session is resumed
  via /chat/resume (continue, not restart). One-shot lock still enforced once decided.
- mock/tests updated: persona deciding buy -> send auto-finishes won.
Rebuilt dist.

frontend/dist/assets/arrow-left-haz-8IhO.js

@@ -0,0 +1,6 @@
+import{k as e}from"./index-Dv9XjhnS.js";/**
+ * @license lucide-vue-next v1.0.0 - ISC
+ *
+ * This source code is licensed under the ISC license.
+ * See the LICENSE file in the root directory of this source tree.
+ */const t=e("arrow-left",[["path",{d:"m12 19-7-7 7-7",key:"1l729n"}],["path",{d:"M19 12H5",key:"x3x0zl"}]]);export{t as A};