ci: self-bootstrap repo (clone-if-absent) on fresh hosts

Deploy assumed the repo was pre-cloned at ~/<name>; clone it over HTTPS+token
if absent so a brand-new host self-assembles.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

.gitea/workflows/build-deploy-game.yml

@@ -144,6 +144,7 @@ jobs:
           envs: GAME_ID
           script: |
             docker login git.unom.io -u ${{ secrets.REGISTRY_USER }} -p ${{ secrets.REGISTRY_TOKEN }}
+            [ -d ~/${GAME_ID}/.git ] || git clone "https://${{ secrets.REGISTRY_USER }}:${{ secrets.REGISTRY_TOKEN }}@git.unom.io/played/${GAME_ID}.git" ~/${GAME_ID}
             cd ~/${GAME_ID}
             git fetch origin main
             git reset --hard origin/main