Fix tier-based monitoring: Scout users no longer get Tycoon-level checks

Previously, the realtime (10-min) check job would check ALL tiers including
Scout users, giving them free premium service. Now:
- daily: checks ALL tiers (baseline service)
- hourly: checks Trader + Tycoon only
- realtime: checks Tycoon only (premium feature)

backend/app/scheduler.py

@@ -65,14 +65,22 @@ async def check_domains_by_frequency(frequency: str):
     
     async with AsyncSessionLocal() as db:
         # Get users with matching check frequency
+        # IMPORTANT: Higher tiers get MORE frequent checks, not the other way around
+        # - daily: checks ALL tiers (minimum service level for everyone)
+        # - hourly: checks Trader + Tycoon only
+        # - realtime: checks Tycoon only
         tiers_for_frequency = []
         for tier, config in TIER_CONFIG.items():
-            if config['check_frequency'] == frequency:
+            tier_freq = config['check_frequency']
+            
+            if frequency == 'daily':
+                # Daily job checks ALL tiers (this is the baseline)
                 tiers_for_frequency.append(tier)
-            # Realtime includes hourly and daily too (more frequent = superset)
-            elif frequency == 'realtime':
+            elif frequency == 'hourly' and tier_freq in ['hourly', 'realtime']:
+                # Hourly job checks Trader + Tycoon
                 tiers_for_frequency.append(tier)
-            elif frequency == 'hourly' and config['check_frequency'] in ['hourly', 'realtime']:
+            elif frequency == 'realtime' and tier_freq == 'realtime':
+                # Realtime job checks ONLY Tycoon (premium feature)
                 tiers_for_frequency.append(tier)
         
         # Get domains from users with matching subscription tier