Add ownership warning to deploy --reset-data

The script now prints the chown command needed after pushing data,
since uploaded files are owned by admin and the web server can't
write to them. Updated docs to match.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

deploy

@@ -16,6 +16,10 @@ if [ "$1" = "--reset-data" ]; then
     echo "Pushing local data to server..."
     rsync -avz --no-t --no-p \
         data/ ${HOST}:${DIR}/data/
+    echo ""
+    echo "*** Data pushed. Fix ownership so the web server can write: ***"
+    echo "    ssh ${HOST} \"sudo chown -R my_webapp__2:my_webapp__2 ${DIR}/data/\""
+    echo ""
 else
     echo "Pulling data from server..."
     mkdir -p data