feat: Add reusable MaterialFilter component

Provides shape, type, grade dropdowns and text search
for filtering material-based list pages.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

CutList.Web/Components/Shared/MaterialFilter.razor

@@ -0,0 +1,79 @@
+@using CutList.Web.Data.Entities
+
+<div class="row g-2 mb-3">
+    <div class="col-auto">
+        <select class="form-select form-select-sm" value="@Value.Shape" @onchange="OnShapeChanged">
+            <option value="">All Shapes</option>
+            @foreach (var shape in Enum.GetValues<MaterialShape>())
+            {
+                <option value="@shape">@shape.GetDisplayName()</option>
+            }
+        </select>
+    </div>
+    <div class="col-auto">
+        <select class="form-select form-select-sm" value="@Value.Type" @onchange="OnTypeChanged">
+            <option value="">All Types</option>
+            @foreach (var type in Enum.GetValues<MaterialType>())
+            {
+                <option value="@type">@type</option>
+            }
+        </select>
+    </div>
+    <div class="col-auto">
+        <select class="form-select form-select-sm" value="@(Value.Grade ?? "")" @onchange="OnGradeChanged">
+            <option value="">All Grades</option>
+            @foreach (var grade in AvailableGrades)
+            {
+                <option value="@grade">@grade</option>
+            }
+        </select>
+    </div>
+    <div class="col-auto">
+        <input type="text" class="form-control form-control-sm" placeholder="Search..." value="@Value.SearchText" @oninput="OnSearchInput" />
+    </div>
+    <div class="col-auto">
+        <button class="btn btn-sm btn-outline-secondary" @onclick="OnClear" title="Clear filters">
+            <i class="bi bi-x-lg"></i> Clear
+        </button>
+    </div>
+</div>
+
+@code {
+    [Parameter] public IEnumerable<string> AvailableGrades { get; set; } = Enumerable.Empty<string>();
+    [Parameter] public MaterialFilterState Value { get; set; } = new();
+    [Parameter] public EventCallback<MaterialFilterState> ValueChanged { get; set; }
+
+    private async Task OnShapeChanged(ChangeEventArgs e)
+    {
+        Value.Shape = Enum.TryParse<MaterialShape>(e.Value?.ToString(), out var shape) ? shape : null;
+        await ValueChanged.InvokeAsync(Value);
+    }
+
+    private async Task OnTypeChanged(ChangeEventArgs e)
+    {
+        Value.Type = Enum.TryParse<MaterialType>(e.Value?.ToString(), out var type) ? type : null;
+        await ValueChanged.InvokeAsync(Value);
+    }
+
+    private async Task OnGradeChanged(ChangeEventArgs e)
+    {
+        var val = e.Value?.ToString();
+        Value.Grade = string.IsNullOrEmpty(val) ? null : val;
+        await ValueChanged.InvokeAsync(Value);
+    }
+
+    private async Task OnSearchInput(ChangeEventArgs e)
+    {
+        Value.SearchText = e.Value?.ToString();
+        await ValueChanged.InvokeAsync(Value);
+    }
+
+    private async Task OnClear()
+    {
+        Value.Shape = null;
+        Value.Type = null;
+        Value.Grade = null;
+        Value.SearchText = null;
+        await ValueChanged.InvokeAsync(Value);
+    }
+}

CutList.Web/Components/Shared/MaterialFilterState.cs

@@ -0,0 +1,11 @@
+using CutList.Web.Data.Entities;
+
+namespace CutList.Web.Components.Shared;
+
+public class MaterialFilterState
+{
+    public MaterialShape? Shape { get; set; }
+    public MaterialType? Type { get; set; }
+    public string? Grade { get; set; }
+    public string? SearchText { get; set; }
+}