feat: port 3030, add REFRESH_INTERVAL

.env.example

@@ -10,6 +10,7 @@ TRANSITION_DURATION=2
 IMAGE_FIT=contain
 SHUFFLE=true
 BACKGROUND_BLUR=true
+REFRESH_INTERVAL=300
 
 # Overlays
 SHOW_CLOCK=true
@@ -17,9 +18,9 @@ SHOW_DATE=true
 SHOW_EXIF=true
 SHOW_PROGRESS=true
 
-# Auto-start (optional)
+# Auto-start (optional — or use URL params instead)
 # ALBUM_ID=
 # SHOW_FAVORITES_ONLY=false
 
 # Server
-PORT=3000
+PORT=3030