Optimize deploy script

- Zero-downtime PM2 reload instead of stop+start
- Keep .next.prev backup until after health check
- Add standalone static file verification
- Remove duplicate sleep
- Clean up naming

.gitea/workflows/deploy.yaml

@@ -316,13 +316,22 @@ jobs:
             echo "ERROR: stage build produced no .next/" >&2
             exit 1
           fi
+          # Verify standalone static files exist (required by Next.js standalone mode).
+          STANDALONE_STATIC="${STAGE}/.next/standalone/.next/static"
+          if [ -d "${STANDALONE_STATIC}" ] && [ -z "$(ls -A "${STANDALONE_STATIC}" 2>/dev/null)" ]; then
+            echo "WARNING: standalone .next/static is empty — copying fresh..."
+            cp -r "${STAGE}/.next/static/." "${STANDALONE_STATIC}/"
+          elif [ ! -d "${STANDALONE_STATIC}" ]; then
+            echo "WARNING: standalone static dir missing — creating..."
+            mkdir -p "${STANDALONE_STATIC}"
+            cp -r "${STAGE}/.next/static/." "${STANDALONE_STATIC}/"
+          fi
 
           echo "Cutover: stop service (free DB connections), migrate, swap .next..."
           CUTOVER_STARTED=1
           pm2 stop next || true
-          sleep 2
           # Give MariaDB a moment to reclaim the live pool.
-          sleep 2
+          sleep 3
 
           # Migrate only after live is stopped — avoids ER_CON_COUNT_ERROR while
           # the old process still holds DATABASE_POOL_SIZE connections.
@@ -356,8 +365,7 @@ jobs:
           fi
           echo "Verified live src/ matches HEAD"
 
-          # Atomic-ish artifact swap: keep previous .next until the new one is in place.
-          rm -rf .next.prev
+          # Save current .next as backup before swapping (kept until health check passes).
           if [ -d .next ]; then
             mv .next .next.prev
           fi
@@ -372,8 +380,8 @@ jobs:
 
           sudo chown -R www-data:www-data "${LIVE}"
 
-          echo "Starting PM2..."
-          pm2 start next --update-env || pm2 restart next --update-env
+          echo "Starting PM2 (zero-downtime reload)..."
+          pm2 reload next --update-env || pm2 start next --update-env
 
           sleep 3
           if ! pm2 show next 2>/dev/null | grep -q 'online'; then
@@ -402,7 +410,7 @@ jobs:
             exit 1
           fi
 
-          echo "Cleaning stage worktree and previous .next..."
+          echo "Cleaning stage worktree and previous .next backup..."
           rm -rf "${LIVE}/.next.prev"
           git -C "${LIVE}" worktree remove --force "${STAGE}" 2>/dev/null || rm -rf "${STAGE}" || true
           STAGE=""