Add shared frontend primitive components

src/RolemasterDb.App/Components/Primitives/SegmentedTabs.razor

@@ -0,0 +1,45 @@
+<div class="@BuildCssClass()" role="tablist" aria-label="@AriaLabel">
+    @foreach (var item in Items)
+    {
+        var isSelected = string.Equals(item.Value, SelectedValue, StringComparison.Ordinal);
+
+        <button
+            type="button"
+            class="segmented-tabs-button @(isSelected ? "is-selected" : null)"
+            role="tab"
+            aria-selected="@isSelected"
+            disabled="@item.IsDisabled"
+            @onclick="() => SelectAsync(item.Value)">
+            <span>@item.Label</span>
+            @if (!string.IsNullOrWhiteSpace(item.Badge))
+            {
+                <span class="segmented-tabs-badge">@item.Badge</span>
+            }
+        </button>
+    }
+</div>
+
+@code {
+    [Parameter]
+    public IReadOnlyList<SegmentedTabItem> Items { get; set; } = [];
+
+    [Parameter]
+    public string? SelectedValue { get; set; }
+
+    [Parameter]
+    public EventCallback<string> SelectedValueChanged { get; set; }
+
+    [Parameter]
+    public string AriaLabel { get; set; } = "Options";
+
+    [Parameter]
+    public string? CssClass { get; set; }
+
+    private string BuildCssClass() =>
+        string.IsNullOrWhiteSpace(CssClass)
+            ? "segmented-tabs"
+            : $"segmented-tabs {CssClass}";
+
+    private Task SelectAsync(string value) =>
+        SelectedValueChanged.InvokeAsync(value);
+}