fix: warn instead of silent fallback when HEAD lacks x-linked-size

Author: XciD

src/virtual_fs/mod.rs

@@ -457,8 +457,14 @@ impl VirtualFs {
                 };
                 let mut inodes = self.inode_table.write().expect("inodes poisoned");
                 if changed {
-                    let current_size = inodes.get(ino).map_or(0, |e| e.size);
-                    let remote_size = head_info.size.unwrap_or(current_size);
+                    let remote_size = head_info.size.unwrap_or_else(|| {
+                        let fallback = inodes.get(ino).map_or(0, |e| e.size);
+                        warn!(
+                            "HEAD missing x-linked-size for {}, falling back to cached size={}",
+                            full_path, fallback,
+                        );
+                        fallback
+                    });
                     let remote_mtime = head_info
                         .last_modified
                         .as_deref()