feat(pages): help-page (support) queue — stream, snapshot, respond, close

Phase 2 of docs/ADMIN_CONTROLS.md: surface the in-game help-page queue to the
website.

- BridgePages.cs: the queue has no EventSink, so it is polled (PageSweepSeconds,
  default 5s) and diffed, keyed by sender serial (one page per player) ->
  page.new / page.updated / page.closed. Inbound pages.snapshot -> pages.list;
  page.respond delivers a staff reply to the player (online: a gump now; offline:
  queued for next login; shows as "Staff") and can close; page.close removes it.
- BridgeConfig/Bridge.cfg: PageSweepSeconds. BridgeBoot: reload re-arms the poll,
  status reports it.
- sidecar/src/web.rs: GET /pages, POST /pages/{id}/respond, POST /pages/{id}/close.
- INTEGRATION.md: page events (§4) and endpoints (§6).
- tools/scaffolding/BridgePageProbe.cs: gated headless verification.

Verified live (probe-seeded tickets): snapshot returns the queue, the poll emits
page.new for both and page.closed on removal, respond -> 200, close removes the
page, unknown page -> 404.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0114TpmrNW4wNXsHq5CR72jQ

overlay/Scripts/Custom/Bridge/BridgeBoot.cs

@@ -159,6 +159,7 @@ namespace Server.Custom.Bridge
                 case "reload":
                     BridgeConfig.Load();
                     BridgeSweeps.Rearm();
+                    BridgePages.Rearm();
                     e.Mobile.SendMessage("Bridge: {0}", BridgeConfig.Describe());
                     e.Mobile.SendMessage("Bridge: sweeps re-armed; endpoint changes take effect on reconnect.");
                     break;
@@ -181,6 +182,7 @@ namespace Server.Custom.Bridge
                         BridgeLink.Connected, BridgeLink.Depth, BridgeLink.Sent, BridgeLink.Dropped,
                         BridgeLink.Received, BridgeLink.Connects, BridgeLink.WriteErrors);
                     e.Mobile.SendMessage("Bridge: {0}", BridgeSweeps.Status());
+                    e.Mobile.SendMessage("Bridge: {0}", BridgePages.Status());
                     break;
             }
         }