fix(scenario): recontact chats normally first then re-engages mid-chat; channel default=social; remove 'add more' button (15 personas auto)

- recontact persona now opens as a NORMAL customer (no 'I asked before' in the opening);
  the mid-chat time-lapse system note (turn 2) makes them re-engage warmer instead.
- channel default changed facebook->social everywhere (create/analyze/store/simulator/me).
- 15 personas auto-generated (TARGET=15); removed the 'สร้างบุคคลต้นแบบเพิ่มเติม' button/guide.
All 9 backend suites pass. Rebuilt dist.

backend/app/services/simulator.py

@@ -102,21 +102,16 @@ class Simulator:
             "social": "Chat style: short, casual, quick social-messaging replies.",
             "f2f_call": "Style: natural, conversational like a live face-to-face or phone talk.",
         }.get(scenario, "")
-        # Personality trait: a "recontact" customer asked about this before and is only now
-        # coming back, already warmer / more ready to buy. Reference it in chat naturally.
-        if persona.get("recontact"):
-            adapt += (
-                "\nYou contacted/interacted with this seller BEFORE (earlier contact) and are now "
-                "coming back — you already know the product basics, so you're warmer and more ready "
-                "to decide. Mention this naturally (e.g. 'I asked about this a while back')."
-            )
+        # NOTE: 'recontact' is a MID-CHAT behavior, not baked into the opening — the trainee
+        # chats with this customer normally first. At the right turn (see chat_routes) a
+        # time-lapse system note is inserted and only THEN does the customer re-engage warmer.
         tolerance = int(persona.get("tolerance", 3) or 3)
         system = CHAT_SYSTEM.format(
             name=persona.get("name", "Customer"),
             tone=persona.get("communication_style", "natural, casual"),
             profession=persona.get("profession", "customer"),
             age_group=persona.get("age_group", "adult"),
-            channel=persona.get("channel", "facebook") + (f" ({scenario})" if scenario else ""),
+            channel=persona.get("channel", "social") + (f" ({scenario})" if scenario else ""),
             background=persona.get("background", ""),
             personality=persona.get("personality", ""),
             lifestyle=persona.get("lifestyle", ""),