feat(bot): phase-6 calibration — mock seed, A/B harness, low-trust fallback

- tools/seed_mock.py: idempotent additive mock data (uuid5 ids) covering all
  tables (units, brands, specs, suppliers, materials + EAV/brand/unit links,
  projects, warehouses, inventory, quotes with termsheets/line items/decisions,
  receipts) so phases 6-7 can be exercised end-to-end
- tools/calibrate_matching.py: A/B difflib vs Jev on 35 scenarios (31 positive
  + 4 negative); collects RAW picks with widened bands, classifies against the
  configured thresholds, sweeps EXACT 0.55-0.95 (negatives count as binds),
  recommends FLOOR strictly above the highest wrong pick with margin for
  ±0.05 run-to-run confidence jitter; markdown report + real traces
- matching.py: below-FLOOR picks no longer suppress difflib — they log a
  routing.decision event (source=jev-lowtrust) and leave no result so the
  existing difflib path keeps its chance (0.54 «پردیس» was lost to «new»)
- config.py: JEV_CONF_FLOOR 0.60 -> 0.65 (removes the جعبه→بسته @0.61 wrong
  candidate offer; correct sub-floor picks باق اسپارت/کیلو are difflib-covered)
- test_matching.py: +2 low-trust cases (13/13 mock, 16/16 live)
- docker-compose.yml: mount bot/tools into the bot container

bot/app/config.py

@@ -147,7 +147,9 @@ class Settings(BaseSettings):
     JEV_ENABLED: bool = True
     JEV_TIMEOUT: float = 8.0
     JEV_CONF_EXACT: float = 0.85
-    JEV_CONF_FLOOR: float = 0.60
+    JEV_CONF_FLOOR: float = 0.65   # phase-6 calibration (2026-10-12): 0.60 let one
+                                   # wrong candidate (جعبه→بسته @0.61) through; the
+                                   # correct picks it drops are covered by difflib.
     JEV_MAX_QUESTIONS_PER_FIELD: int = 15
 
     LOG_LEVEL: str = "INFO"