Polish AmiReel UI and improve render workflow

AmiReel.WinUI/.github/instructions/performance.instructions.md

@@ -0,0 +1,53 @@
+---
+description: 'Performance requirements for data binding, layout, threading, and collection virtualization'
+applyTo: '**/*.cs, **/*.xaml'
+---
+
+# Performance
+
+These rules apply to **every feature and change**. They are not optional add-ons.
+
+---
+
+## Rules
+
+- **Use `x:Bind`** (compiled bindings) instead of `{Binding}` — it's faster and type-safe.
+- Use **`x:Load`** (or `x:DeferLoadStrategy`) to defer loading of UI elements not immediately visible.
+- Avoid heavy work on the UI thread — use `Task.Run` for CPU-bound work and `async/await` for I/O.
+- Use **virtualizing panels** (`ItemsRepeater` with `StackLayout`, or `ListView`) for long lists — never use `StackPanel` with hundreds of items.
+- **Cache** expensive computations and HTTP responses when appropriate.
+- Minimize XAML visual tree depth — deep nesting hurts layout performance.
+- Use **incremental loading** (`ISupportIncrementalLoading`) for large data sets.
+- Profile with **Visual Studio Diagnostics Tools** and **PerfView** before and after optimizations.
+- Be cautious with `DispatcherQueue.TryEnqueue` — don't flood the dispatcher queue.
+
+## Anti-patterns
+
+- Blocking the UI thread with `.Result` or `.GetAwaiter().GetResult()`.
+- Loading all data upfront when only a subset is needed.
+- Creating new `HttpClient` instances per request (use `IHttpClientFactory`).
+- Using `FindName()` or `VisualTreeHelper` in tight loops.
+
+## Validation
+
+- Build & register the MSIX package — see **Build, Run & Deploy** in `.github/agents/Agents.md`.
+
+### Verification Checklist
+
+- [ ] No blocking calls on the UI thread
+- [ ] `x:Bind` is used instead of `{Binding}`
+- [ ] Large lists use virtualization
+
+## Must Read & Research
+
+> **Agent Rule:** Before any performance-sensitive change (data binding, layout, collections, async), you **must** fetch and review these references using `fetch_webpage`. Apply what you learn.
+
+| # | Reference | When to consult |
+|---|---|---|
+| 1 | [Performance best practices for WinUI 3](https://learn.microsoft.com/en-us/windows/apps/performance/) | Any change touching UI rendering, data loading, or threading |
+| 2 | [x:Bind markup extension](https://learn.microsoft.com/en-us/windows/uwp/xaml-platform/x-bind-markup-extension) | Adding or modifying XAML data bindings |
+| 3 | [x:Load attribute](https://learn.microsoft.com/en-us/windows/uwp/xaml-platform/x-load-attribute) | Deferring UI element loading |
+| 4 | [Optimize XAML layout](https://learn.microsoft.com/en-us/windows/apps/performance/optimize-xaml-layout) | Restructuring XAML panels, reducing visual tree depth |
+| 5 | [ListView optimization](https://learn.microsoft.com/en-us/windows/apps/performance/optimize-listview) | Working with lists, collections, or `ItemsRepeater` |
+
+