Simplify Organize Models dialog layout

Consolidate the busy header into a single column flow: drop the
side-by-side Preview card, merge the count pills + filter checkboxes
into one row of clickable filter chips with an accent-bordered
selected state, inline the metadata warning as a slim banner, and
swap the Variables expander for a teaching tip with a toggle button
on the pattern textbox.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: mohnjiles

StabilityMatrix.Avalonia/ViewModels/Dialogs/OrganizeModelsDialogViewModel.cs

@@ -54,12 +54,17 @@ ModelOrganizationService modelOrganizationService
 
     [ObservableProperty]
     [NotifyPropertyChangedFor(nameof(ShowMissingMetadataWarning))]
+    [NotifyPropertyChangedFor(nameof(ShowMetadataActions))]
     public partial int MissingMetadataCount { get; set; }
 
     [ObservableProperty]
     [NotifyPropertyChangedFor(nameof(ShowIncompleteMetadataWarning))]
+    [NotifyPropertyChangedFor(nameof(ShowMetadataActions))]
     public partial int IncompleteMetadataCount { get; set; }
 
+    [ObservableProperty]
+    public partial bool IsVariablesTipOpen { get; set; }
+
     [ObservableProperty]
     public partial bool ShowReadyItems { get; set; } = true;
 
@@ -83,6 +88,8 @@ ModelOrganizationService modelOrganizationService
 
     public bool ShowIncompleteMetadataWarning => IncompleteMetadataCount > 0;
 
+    public bool ShowMetadataActions => ShowMissingMetadataWarning || ShowIncompleteMetadataWarning;
+
     public string ReadySummary =>
         Plan == null
             ? string.Empty
@@ -205,14 +212,20 @@ private void UpdatePreviewSample()
     public override BetterContentDialog GetDialog()
     {
         var dialog = base.GetDialog();
-        dialog.MinDialogWidth = 900;
-        dialog.MaxDialogHeight = 800;
+        dialog.MinDialogWidth = 1120;
+        dialog.MaxDialogHeight = 900;
         dialog.IsFooterVisible = false;
         dialog.CloseOnClickOutside = true;
         dialog.ContentVerticalScrollBarVisibility = ScrollBarVisibility.Disabled;
         return dialog;
     }
 
+    [RelayCommand]
+    private void OpenVariablesTip() => IsVariablesTipOpen = true;
+
+    [RelayCommand]
+    private void ToggleVariablesTip() => IsVariablesTipOpen = !IsVariablesTipOpen;
+
     [RelayCommand(CanExecute = nameof(CanOrganize))]
     private void ConfirmOrganize()
     {