Monorepo: consolidate 7 repos into one

Combines shared, blog, market, cart, events, federation, and account
into a single repository. Eliminates submodule sync, sibling model
copying at build time, and per-app CI orchestration.

Changes:
- Remove per-app .git, .gitmodules, .gitea, submodule shared/ dirs
- Remove stale sibling model copies from each app
- Update all 6 Dockerfiles for monorepo build context (root = .)
- Add build directives to docker-compose.yml
- Add single .gitea/workflows/ci.yml with change detection
- Add .dockerignore for monorepo build context
- Create __init__.py for federation and account (cross-app imports)

.gitea/workflows/ci.yml

@@ -0,0 +1,72 @@
+name: Build and Deploy
+
+on:
+  push:
+    branches: [main, decoupling]
+
+env:
+  REGISTRY: registry.rose-ash.com:5000
+  COOP_DIR: /root/rose-ash
+
+jobs:
+  build-and-deploy:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install tools
+        run: |
+          apt-get update && apt-get install -y --no-install-recommends openssh-client
+
+      - name: Set up SSH
+        env:
+          SSH_KEY: ${{ secrets.DEPLOY_SSH_KEY }}
+          DEPLOY_HOST: ${{ secrets.DEPLOY_HOST }}
+        run: |
+          mkdir -p ~/.ssh
+          echo "$SSH_KEY" > ~/.ssh/id_rsa
+          chmod 600 ~/.ssh/id_rsa
+          ssh-keyscan -H "$DEPLOY_HOST" >> ~/.ssh/known_hosts 2>/dev/null || true
+
+      - name: Build and deploy changed apps
+        env:
+          DEPLOY_HOST: ${{ secrets.DEPLOY_HOST }}
+        run: |
+          ssh "root@$DEPLOY_HOST" "
+            cd ${{ env.COOP_DIR }}
+            git fetch origin ${{ github.ref_name }}
+
+            # Detect what changed since current HEAD
+            CHANGED=\$(git diff --name-only HEAD origin/${{ github.ref_name }})
+            git reset --hard origin/${{ github.ref_name }}
+
+            REBUILD_ALL=false
+            if echo \"\$CHANGED\" | grep -q '^shared/'; then
+              REBUILD_ALL=true
+            fi
+            if echo \"\$CHANGED\" | grep -q '^docker-compose.yml'; then
+              REBUILD_ALL=true
+            fi
+
+            for app in blog market cart events federation account; do
+              if [ \"\$REBUILD_ALL\" = true ] || echo \"\$CHANGED\" | grep -q \"^\$app/\"; then
+                echo \"Building \$app...\"
+                docker build \
+                  --build-arg CACHEBUST=\$(date +%s) \
+                  -f \$app/Dockerfile \
+                  -t ${{ env.REGISTRY }}/\$app:latest \
+                  -t ${{ env.REGISTRY }}/\$app:${{ github.sha }} \
+                  .
+                docker push ${{ env.REGISTRY }}/\$app:latest
+                docker push ${{ env.REGISTRY }}/\$app:${{ github.sha }}
+              else
+                echo \"Skipping \$app (no changes)\"
+              fi
+            done
+
+            source .env
+            docker stack deploy -c docker-compose.yml coop
+            echo 'Waiting for services to update...'
+            sleep 10
+            docker stack services coop
+          "