PUBG drop map: live squad map with WebSocket rooms

- server.js wraps Bun.serve to add /ws/<channel> upgrades (same server and port) and
  serve the map tiles from the host mount; Dockerfile now runs bun ./server.js
- ws hub (channel registry, origin check) + pubg-map channel: rooms by unguessable
  code, validated + rate-limited messages, per-room write queue, presence
- games.pubg_rooms / pubg_matches / pubg_markers; per-match sessions with history
- /trackers/games/pubg/map hub (owner: rooms, landings over time, history) and
  /trackers/games/pubg/map/<code> fullscreen Leaflet map (all 11 maps)
- deploy-remote.sh bind-mounts ~/pubg-maps; scripts/build-pubg-tiles.py rebuilds it

scripts/deploy-remote.sh

@@ -83,6 +83,31 @@ YAML
 else
   echo "No $money_documents_host_dir/documents.json on this host; money documents will not be readable" >&2
 fi
+# PUBG drop map tiles (512 px WebP, from PUBG's official api-assets) also live on the host,
+# outside the repo (~120 MB), bind-mounted read-only at /pubg-maps; server.js serves them at
+# /pubg-tiles/<map>/<z>/<x>/<y>.webp. Layout: <map>/<z>/<x>/<y>.webp + <map>/thumb.webp.
+pubg_tiles_host_dir=${PUBG_TILES_HOST_DIR:-/home/stan/pubg-maps}
+case "$pubg_tiles_host_dir" in /*) ;; *) echo 'PUBG_TILES_HOST_DIR must be absolute' >&2; exit 2 ;; esac
+if sudo docker run --rm --entrypoint sh \
+  --mount "type=bind,source=$pubg_tiles_host_dir,target=/pubg-maps,readonly" "$image" \
+  -c 'test -f /pubg-maps/erangel/thumb.webp' 2>/dev/null; then
+  pubg_tiles_override="$HOME/compose.pubg-tiles.yml"
+  rm -f "$pubg_tiles_override"
+  cat >"$pubg_tiles_override" <<YAML
+services:
+  app:
+    environment:
+      PUBG_TILES_ROOT: /pubg-maps
+    volumes:
+      - type: bind
+        source: $pubg_tiles_host_dir
+        target: /pubg-maps
+        read_only: true
+YAML
+  compose_files+=(-f "$pubg_tiles_override")
+else
+  echo "No $pubg_tiles_host_dir/erangel on this host; the PUBG map will have no tiles" >&2
+fi
 previous_tag=$(sed -n 's/^IMAGE_TAG=//p' "$directory/.env" | head -n 1)
 switched=0
 rollback() {