Revert MudBlazor to 6.18.0 & Fix app bar text color

- Filled buttons always have the hover style
- Hover effects are too faint on the header buttons
Both are a side effect of MudBlazor/MudBlazor#8405

But we still get to keep the "sticky" hover fix in 6.18.0.

JournalApp/JournalApp.csproj

@@ -60,7 +60,7 @@
     <PackageReference Include="Microsoft.Extensions.Logging.Debug" Version="8.0.0" />
     <PackageReference Include="Microsoft.Maui.Controls" Version="$(MauiVersion)" />
     <PackageReference Include="Microsoft.Maui.Controls.Compatibility" Version="$(MauiVersion)" />
-    <PackageReference Include="MudBlazor" Version="6.19.1" />
+    <PackageReference Include="MudBlazor" Version="6.18.0" />
     <PackageReference Include="Nerdbank.GitVersioning" Version="3.6.133" PrivateAssets="All" />
   </ItemGroup>
 

JournalApp/wwwroot/app.css

@@ -55,6 +55,10 @@ body {
   --mud-palette-action-default: var(--mud-palette-appbar-text);
 }
 
+  .page-header *.mud-typography {
+    color: var(--mud-palette-appbar-text);
+  }
+
 .mud-dialog .mud-dialog-title, .page-title {
   z-index: 999;
   display: flex;
@@ -67,6 +71,10 @@ body {
   --mud-palette-action-default: var(--mud-palette-appbar-text);
 }
 
+  .mud-dialog .mud-dialog-title, .page-title *.mud-typography {
+    color: var(--mud-palette-appbar-text);
+  }
+
 .mud-dialog .mud-dialog-content, .page-body {
   max-width: 960px;
   margin: 0 auto !important;