feat(postal): add postal service addon and bundle pending addon work

- New postal-service-addon: per-player mailboxes + post-office send block
  (ActionForm recipient picker, offline notification queue, chunk-load
  retry via tickingarea)
- Commit previously untracked private-chest, home-sign, keep-inventory
  addons and their docker-compose mounts
- Deploy workflow: add postal + previously unwired addons to path filter
  and checkout list; drop easter-egg from deployment
- enabled_packs.json: register postal UUIDs for Lyla + Mya

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

.gitea/workflows/deploy.yml

@@ -7,8 +7,12 @@ on:
       - 'addon/**'
       - 'lobby-addon/**'
       - 'hub-return-addon/**'
-      - 'easter-egg-addon/**'
       - 'village-evolution-addon/**'
+      - 'monkey-addon/**'
+      - 'private-chest-addon/**'
+      - 'home-sign-addon/**'
+      - 'keep-inventory-addon/**'
+      - 'postal-service-addon/**'
       - 'docker-compose.yml'
       - 'scripts/**'
 
@@ -26,6 +30,7 @@ jobs:
           script: |
             set -e
             APP_DIR="$HOME/minecraft-multiworld"
+            PATHS="addon/ lobby-addon/ hub-return-addon/ village-evolution-addon/ monkey-addon/ private-chest-addon/ home-sign-addon/ keep-inventory-addon/ postal-service-addon/ docker-compose.yml"
 
             # First run: clone. Subsequent: pull.
             if [ ! -d "$APP_DIR/.git" ]; then
@@ -33,11 +38,11 @@ jobs:
               git init
               git remote add origin https://git.silverlabs.uk/SilverLABS/minecraft-aiworld.git
               git fetch origin main
-              git checkout -f origin/main -- addon/ lobby-addon/ hub-return-addon/ easter-egg-addon/ village-evolution-addon/ docker-compose.yml
+              git checkout -f origin/main -- $PATHS
             else
               cd "$APP_DIR"
               git fetch origin main
-              git checkout -f origin/main -- addon/ lobby-addon/ hub-return-addon/ easter-egg-addon/ village-evolution-addon/ docker-compose.yml
+              git checkout -f origin/main -- $PATHS
             fi
 
             # Recreate containers so any new docker-compose volume mounts are applied,