add: post image uploads (supporter)

crates/core/src/model/communities.rs

@@ -236,6 +236,8 @@ pub struct Post {
     pub likes: isize,
     pub dislikes: isize,
     pub comment_count: usize,
+    /// IDs of all uploads linked to this post.
+    pub uploads: Vec<usize>,
 }
 
 impl Post {
@@ -257,6 +259,7 @@ impl Post {
             likes: 0,
             dislikes: 0,
             comment_count: 0,
+            uploads: Vec::new(),
         }
     }