Add cs.money worker stack with per-worker IPRoyal residential proxy

Brings up the pull-model scraper: the .NET C2 hands skin+wear jobs to Python nodriver workers that scrape cs.money and post results back, plus the supporting Core/EFCore data model, migrations, and docker-compose orchestration.

IPRoyal proxying lets workers scale horizontally with a distinct residential exit IP each: every worker process mints its own sticky session at startup, and an in-process forwarding proxy injects the gateway auth so Chromium talks only to an auth-free localhost endpoint (zero CDP). On a Cloudflare challenge a worker rotates to a fresh session/IP and re-warms. Verified end-to-end against live IPRoyal: distinct US residential exits per worker and IP rotation on demand.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

BlueLaminate/BlueLaminate.EFCore/Entities/SkinCondition.cs

@@ -10,6 +10,12 @@ public class SkinCondition
     public decimal MinFloat { get; set; }
     public decimal MaxFloat { get; set; }
 
+    // When the catalogue-driven listing sweep last fully covered this skin's wear
+    // band. The sweep splits each skin by wear and pages one band at a time, so this
+    // is the per-band checkpoint: an interrupted run resumes from never-swept/stalest
+    // bands rather than redoing a whole skin. Null until the first sweep reaches it.
+    public DateTimeOffset? ListingsSweptAt { get; set; }
+
     public ICollection<SkinInstance> Instances { get; set; } = new List<SkinInstance>();
     public ICollection<PriceHistory> PriceHistories { get; set; } = new List<PriceHistory>();
 }