feat(games): support non-steam games

polylan_submitter/games/models.py

@@ -2,9 +2,10 @@ from django.db import models
 
 
 class Game(models.Model):
-    steam_app_id = models.PositiveIntegerField(unique=True)
+    steam_app_id = models.PositiveIntegerField(null=True, blank=True)
     name = models.CharField(max_length=255)
     path = models.CharField(max_length=100)
+    image = models.URLField(null=True, blank=True)
     enabled = models.BooleanField(default=True)
 
     created_at = models.DateTimeField(auto_now_add=True)
@@ -14,4 +15,6 @@ class Game(models.Model):
         ordering = ["name"]
 
     def __str__(self) -> str:
-        return f"{self.name} ({self.steam_app_id})"
+        if self.steam_app_id:
+            return f"{self.name} ({self.steam_app_id})"
+        return self.name