Enhance inject_options function to copy server.properties and server icon to run directory

chipper

@@ -67,6 +67,16 @@ inject_options() {
   if [[ -f "./config/servers.dat" ]]; then
     cp "./config/servers.dat" "$dir/servers.dat"
   fi
+
+  # server.properties
+  if [[ -f "./config/server.properties" ]]; then
+    cp "./config/server.properties" "$dir/server.properties"
+  fi
+
+  # server icon
+  if [[ -f "./config/server-icon.png" ]]; then
+    cp "./config/server-icon.png" "$dir/server-icon.png"
+  fi
 }
 
 ensure_server_files() {