Add SwarmUI settings management and portrait generation enhancements

- Introduced new API endpoints for managing SwarmUI settings, including fetching and saving presets and age rules.
- Updated the portrait generation logic to utilize the new settings structure, allowing for dynamic preset selection based on age.
- Enhanced UI components to support SwarmUI settings, including localization for new strings and improved styling for settings sections.
- Added tests to verify the functionality of new settings endpoints and portrait generation behavior.

This commit lays the groundwork for more flexible and user-friendly portrait generation options.

src/HSchool.Server/Api/SchoolEndpoints.cs

@@ -295,7 +295,9 @@ internal static class SchoolEndpoints
                     PortraitKindParser.ToApiValue(result.Kind),
                     result.Positive,
                     result.Negative,
-                    result.PromptExtra)),
+                    result.PromptExtra,
+                    result.PresetId,
+                    result.PresetLabel)),
                 PortraitPromptBuildOutcome.InvalidPrompt =>
                     Problem(StatusCodes.Status400BadRequest, "invalid-body", "Custom portraits need a non-empty promptExtra up to 2000 characters."),
                 PortraitPromptBuildOutcome.UnknownPerson =>