feat(bridge): publish the player-vendor market index as vendor.listing

Protocol 3.0 §8. Every player vendor's shop name, owner, location and priced
inventory, so the website can offer the search the in-game Vendor Search gump
offers — from outside the game, and honouring the same per-player opt-out.

It cannot be an RPC. rpc.rs correlates a reply on the FIRST frame carrying a
matching reqId, so a chunked reply sharing one reqId would deliver chunk 1 to the
HTTP caller and leak chunks 2..N onto the broadcast feed; a whole-world snapshot
would not fit in one frame inside the 10 s timeout either. So it is a diff sweep
on the broadcast stream, one authoritative frame per vendor.

The one genuinely new pattern here is an amortized round-robin: every other sweep
walks its whole collection per tick, which is fine for tens of houses and is not
fine for a world of shops whose inventories recurse into containers.
MarketSweepBatch (25) vendors are inventoried per tick from a persistent cursor,
so per-tick cost is bounded by the batch rather than by world size.

VendorSearch.GetItemName is never called: it builds an ObjectPropertyList,
serialises it and byte-parses the packet per item. The frame carries itemId, hue,
amount, price, the plain item.Name field and item.LabelNumber; the website
resolves names against its own cliloc table. (It would not work anyway — every
current client ships its cliloc files compressed and ServUO's Ultima.StringList
cannot read them, so the in-game gump has the same gap.)

Measured on the live shard (27 vendors x 40 listings, 209k items / 43k mobiles):
15.4 ms for the first cold tick of 25 vendors, 3.4 ms for the next, 0.3 ms in
steady state. `[bridge status` now reports lastMs/maxMs and a tick over 50 ms
warns, naming the knob — the batch cap is a claim about that number and an
operator tuning it was otherwise tuning blind.

- location is ONE nested object, not flat map/x/y/region, so the website's single
  market.location visibility rule can hide a vendor's whereabouts on both the
  live frame and the stored read model. Flat keys would need five rules.
- Owner is flat ownerSerial/ownerName, never BridgeJson.Actor, which would add
  acct and webId. Same argument points.board makes.
- pv.VendorSearch is honoured, so a shop hidden in game is hidden on the site;
  the seen-set removal then emits vendor.listing.remove.
- Container-priced items carry child:true, exactly as DoSearch reports them.
- Over MarketMaxListings (250) the frame says truncated and carries the real
  total, so the site shows "250 of 3,104" rather than a partial shop as complete.

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

overlay/Scripts/Custom/Bridge/BridgeBoot.cs

@@ -166,6 +166,7 @@ namespace Server.Custom.Bridge
                     BridgePresence.Rearm();
                     BridgeHousing.Rearm();
                     BridgePoints.Rearm();
+                    BridgeMarket.Rearm();
                     // Not a sweep, so it has nothing to re-arm — but an operator who just edited a
                     // .cfg wants the change on the site now, not after a shard restart.
                     BridgeRuleset.Emit();
@@ -186,6 +187,7 @@ namespace Server.Custom.Bridge
                     BridgePresence.SweepOnce();
                     BridgeHousing.SweepOnce();
                     BridgePoints.SweepOnce();
+                    BridgeMarket.SweepOnce();
                     e.Mobile.SendMessage("Bridge: ran one sweep of each stream.");
                     e.Mobile.SendMessage("Bridge: {0}", BridgeSweeps.Status());
                     e.Mobile.SendMessage("Bridge: {0}", BridgeChamps.Status());
@@ -194,6 +196,7 @@ namespace Server.Custom.Bridge
                     e.Mobile.SendMessage("Bridge: {0}", BridgePresence.Status());
                     e.Mobile.SendMessage("Bridge: {0}", BridgeHousing.Status());
                     e.Mobile.SendMessage("Bridge: {0}", BridgePoints.Status());
+                    e.Mobile.SendMessage("Bridge: {0}", BridgeMarket.Status());
                     break;
 
                 default:
@@ -209,6 +212,7 @@ namespace Server.Custom.Bridge
                     e.Mobile.SendMessage("Bridge: {0}", BridgePresence.Status());
                     e.Mobile.SendMessage("Bridge: {0}", BridgeHousing.Status());
                     e.Mobile.SendMessage("Bridge: {0}", BridgePoints.Status());
+                    e.Mobile.SendMessage("Bridge: {0}", BridgeMarket.Status());
                     e.Mobile.SendMessage("Bridge: {0}", BridgePages.Status());
                     e.Mobile.SendMessage("Bridge: {0}", BridgeRuleset.Status());
                     break;