Render FAQ topics as cards, drop dead scoped CSS

Elternbeirat.Contracts/FaqTopic.cs

@@ -38,7 +38,7 @@ public record FaqTopic
     public required string Title { get; init; }
 
     /// <summary>
-    ///     Gets the URL slug of the topic, e.g. <c>"mensa"</c>.
+    ///     Gets the URL slug of the topic, e.g. <c>"cafeteria"</c>.
     /// </summary>
     /// <value>
     ///     A URL path segment: lowercase letters, digits and single hyphens as
@@ -70,4 +70,49 @@ public record FaqTopic
     /// </value>
     [JsonPropertyName("order")]
     public double Order { get; init; }
+
+    /// <summary>
+    ///     Gets the expanded relations returned by PocketBase, or <see langword="null"/>
+    ///     when the query did not expand any.
+    /// </summary>
+    [JsonPropertyName("expand")]
+    public FaqTopicExpand? Expand { get; init; }
+
+    /// <summary>
+    ///     Gets the questions of this topic, ordered by <see cref="Faq.Order"/>, or an
+    ///     empty list when none are linked or the relation was not expanded.
+    /// </summary>
+    /// <remarks>
+    ///     Convenience over <see cref="Expand"/>: questions name their topic, so
+    ///     PocketBase returns them under the back-relation key when the query expands it
+    ///     (<c>faqs_via_topic</c>). The topic detail page reads them from here. They
+    ///     arrive unsorted, so this orders them by <see cref="Faq.Order"/> for a stable
+    ///     render. Drafts are dropped: PocketBase does not apply the topic query's
+    ///     <c>public</c> filter to the expanded children, so this keeps
+    ///     non-public questions (<see cref="Faq.Public"/>) off the page.
+    /// </remarks>
+    [JsonIgnore]
+    public IReadOnlyList<Faq> Faqs =>
+        Expand?.Faqs is { } faqs
+            ? [.. faqs.Where(faq => faq.Public).OrderBy(faq => faq.Order)]
+            : [];
+}
+
+/// <summary>
+///     The relations of a <see cref="FaqTopic"/> that PocketBase returns under
+///     <c>expand</c> when the query asks for them.
+/// </summary>
+/// <remarks>
+///     The questions point at their topic, so PocketBase exposes them as the
+///     back-relation <c>faqs_via_topic</c>. <see cref="FaqTopic.Faqs"/> reads through
+///     this.
+/// </remarks>
+public record FaqTopicExpand
+{
+    /// <summary>
+    ///     Gets the expanded questions of the <c>faqs_via_topic</c> back-relation, if it
+    ///     was expanded.
+    /// </summary>
+    [JsonPropertyName("faqs_via_topic")]
+    public IReadOnlyList<Faq>? Faqs { get; init; }
 }