make media_group_id column optional

migrations/2025-04-18-101829_optional_media_group_id/down.sql

@@ -0,0 +1 @@
+ALTER TABLE media ALTER COLUMN media_group_id SET NOT NULL;

migrations/2025-04-18-101829_optional_media_group_id/up.sql

@@ -0,0 +1 @@
+ALTER TABLE media ALTER COLUMN media_group_id DROP NOT NULL;

src/db/models.rs

@@ -31,7 +31,7 @@ pub struct Media {
     pub token: String,
     pub media_type: String,
     pub file_id: String,
-    pub media_group_id: String,
+    pub media_group_id: Option<String>,
 }
 
 #[derive(Queryable, Debug, Identifiable)]

src/db/schema.rs

@@ -22,7 +22,7 @@ diesel::table! {
         token -> Varchar,
         media_type -> Varchar,
         file_id -> Varchar,
-        media_group_id -> Varchar,
+        media_group_id -> Nullable<Varchar>,
     }
 }