Task #710: Weekly availability intervals (Calendly-style) for protocol booking slots

- DB: protocol_booking_slots.days_of_week integer[] NOT NULL default {0..6} (0=Sun..6=Sat, Riyadh); pushed via drizzle-kit, legacy rows keep all-days behaviour.
- API (routes/protocol.ts): slot create/patch accept daysOfWeek (validated, deduped, sorted); new POST /protocol/booking-slots/generate (requireManageRooms) generates stepped slots in [from,to); duplicate rule is day-scoped: same start time on a different day merges the days into the existing slot (existing duration kept), fully covered times skipped; returns {created,merged,skipped,slots}; manual POST create also merges disjoint days instead of 409; matchesActiveSlot and public availability filter by Riyadh weekday.
- UI (protocol.tsx): interval-generation form (from/to/duration + day toggle pills + workdays/all-days presets), toast shows created/merged/skipped, slot list shows day names, booking dialog filters slots by chosen date weekday with stale-selection reset and empty-day hint. i18n keys added (ar/en).
- Tests: 13/13 pass incl. generation, day-scoped merge (same time different day is NOT a duplicate), duplicate skipping, validation, weekday filtering in availability + booking rejection, viewer 403 on generate.

artifacts/tx-os/src/locales/ar.json

@@ -1930,10 +1930,10 @@
       "intervalFrom": "من",
       "intervalTo": "إلى",
       "generate": "توليد الأوقات",
-      "generated": "تم توليد {{created}} وقتًا (تم تجاهل {{skipped}} مكررًا)",
-      "generatedNone": "لم يتولد أي وقت — كل الأوقات موجودة مسبقًا.",
+      "generated": "تم توليد {{created}} وقتًا، ودمج الأيام في {{merged}}، وتجاهل {{skipped}} مكررًا.",
+      "generatedNone": "لا جديد — كل الأوقات والأيام موجودة مسبقًا.",
       "pickDay": "اختر يومًا واحدًا على الأقل",
       "noSlotsForDay": "لا توجد أوقات متاحة في هذا اليوم"
     }
   }
-}
+}