feat(ui): conflict resolver shows why Continue is disabled

Continue was already gated on CanContinue (all files resolved); surface a
footer hint counting the still-unresolved conflicts/files so the disabled
state is explained, not just for binary files.

src/ClaudeDo.Ui/ViewModels/Conflicts/ConflictResolverViewModel.cs

@@ -103,9 +103,19 @@ public sealed partial class ConflictResolverViewModel : ObservableObject
         }
     }
 
-    public string ContinueHint => HasBinaryFiles
-        ? "Binary conflicts must be resolved externally — abort and resolve in your editor."
-        : "";
+    public string ContinueHint
+    {
+        get
+        {
+            if (HasBinaryFiles)
+                return "Binary conflicts must be resolved externally — abort and resolve in your editor.";
+            var openFiles = Files.Count(f => !f.AllResolved);
+            if (openFiles == 0) return "";
+            var openConflicts = _flat.Count(x => !x.Block.IsResolved);
+            return $"{openConflicts} {(openConflicts == 1 ? "conflict" : "conflicts")} in " +
+                   $"{openFiles} {(openFiles == 1 ? "file" : "files")} still unresolved.";
+        }
+    }
 
     private bool InRange => CurrentIndex >= 0 && CurrentIndex < _flat.Count;
 
@@ -188,6 +198,7 @@ public sealed partial class ConflictResolverViewModel : ObservableObject
         OnPropertyChanged(nameof(HasBinaryFiles));
         OnPropertyChanged(nameof(HasMultipleFiles));
         OnPropertyChanged(nameof(FilesSummary));
+        OnPropertyChanged(nameof(ContinueHint));
         RecomputeCanContinue();
         if (_flat.Count > 0)
             MoveTo(0); // also sets ActiveFile via MoveTo
@@ -211,6 +222,7 @@ public sealed partial class ConflictResolverViewModel : ObservableObject
             OnPropertyChanged(nameof(PositionText));
             OnPropertyChanged(nameof(ActiveResultText));
             OnPropertyChanged(nameof(FilesSummary));
+            OnPropertyChanged(nameof(ContinueHint));
         }
     }