ci: pick dir by branch for staging/prod deploy

.gitea/workflows/build.yml

@@ -32,6 +32,14 @@ jobs:
           chmod 600 ~/.ssh/id_ed25519
           ssh-keyscan -H 172.17.0.1 >> ~/.ssh/known_hosts
 
+      - name: pick target
+        run: |
+          if [ "${{ github.ref_name }}" = "main" ]; then
+            echo "DIR=/opt/personal-website" >> $GITHUB_ENV
+          else
+            echo "DIR=/opt/personal-website-staging" >> $GITHUB_ENV
+          fi
+
       - name: deploy
         run: |
-          ssh deploy@172.17.0.1 "echo IMAGE_TAG=${{ github.sha }} | sudo tee /opt/personal-website/.env && sudo docker compose -f /opt/personal-website/compose.prod.yml up -d"
+          ssh deploy@172.17.0.1 "echo IMAGE_TAG=${{ github.sha }} | sudo tee $DIR/.env && sudo docker compose -f $DIR/compose.prod.yml up -d"