feat: A-frame tent + portal walk-through field + texture polish

- camping: replace cube tent with A-frame slope panels (tent_panel_l/r) +
  cardinal_direction permutations; vote-skip sleep that mixes
  player.isSleeping bed sleepers with tent occupants and respects the
  playersSleepingPercentage gamerule; new weathered-canvas texture.
- lobby: walk-through silverlabs:portal_field block (no collision,
  translucent swirl, cross-plane geo) auto-placed above each portal frame;
  invisible silverlabs:portal_label entity floats above each portal with
  the destination world name; transfer detection now scans down through
  the field to find the destination frame.
- postal: regenerate post_office and mailbox block textures so they fill
  the full block face (brick + POST plaque, full red panel with slot/latch
  /flag/rivets) instead of small sprites floating on transparent.
- dynamite + tow-boat: ship the addons (volumes wired into all four
  worlds; enabled_packs registers them into Mya's world).
- art: build-textures.py extended; build-art-catalog.py added to project.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

tow-boat-addon/tow_boat_RP/models/entity/tow_boat.geo.json

@@ -0,0 +1,105 @@
+{
+  "format_version": "1.12.0",
+  "minecraft:geometry": [
+    {
+      "description": {
+        "identifier": "geometry.tow_boat",
+        "texture_width": 64,
+        "texture_height": 32,
+        "visible_bounds_width": 3,
+        "visible_bounds_height": 2,
+        "visible_bounds_offset": [0, 0.5, 0]
+      },
+      "bones": [
+        {
+          "name": "root",
+          "pivot": [0, 0, 0]
+        },
+        {
+          "name": "hull",
+          "parent": "root",
+          "pivot": [0, 0, 0],
+          "cubes": [
+            {
+              "origin": [-11, 0, -16],
+              "size": [22, 3, 32],
+              "uv": [0, 0]
+            }
+          ]
+        },
+        {
+          "name": "deck",
+          "parent": "hull",
+          "pivot": [0, 3, 0],
+          "cubes": [
+            {
+              "origin": [-11, 3, -16],
+              "size": [22, 1, 32],
+              "uv": [0, 16]
+            }
+          ]
+        },
+        {
+          "name": "rail_left",
+          "parent": "deck",
+          "pivot": [-11, 4, 0],
+          "cubes": [
+            {
+              "origin": [-12, 4, -16],
+              "size": [1, 2, 32],
+              "uv": [0, 18]
+            }
+          ]
+        },
+        {
+          "name": "rail_right",
+          "parent": "deck",
+          "pivot": [11, 4, 0],
+          "cubes": [
+            {
+              "origin": [11, 4, -16],
+              "size": [1, 2, 32],
+              "uv": [0, 18]
+            }
+          ]
+        },
+        {
+          "name": "rail_front",
+          "parent": "deck",
+          "pivot": [0, 4, -16],
+          "cubes": [
+            {
+              "origin": [-11, 4, -17],
+              "size": [22, 2, 1],
+              "uv": [0, 22]
+            }
+          ]
+        },
+        {
+          "name": "rail_back",
+          "parent": "deck",
+          "pivot": [0, 4, 16],
+          "cubes": [
+            {
+              "origin": [-11, 4, 16],
+              "size": [22, 2, 1],
+              "uv": [0, 22]
+            }
+          ]
+        },
+        {
+          "name": "tow_post",
+          "parent": "deck",
+          "pivot": [0, 4, -14],
+          "cubes": [
+            {
+              "origin": [-1, 4, -15],
+              "size": [2, 4, 2],
+              "uv": [44, 16]
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}