feat: camera-restore + LauncherUI UX 개선 + player fallback 강화 (#15)

camera-restore:
- IEngineStateProvider.SetCamera 반사 쓰기 (HmegDirectStateProvider)
- POST /camera/restore (BridgeHttpServer, StateRouter)
- Recorder --sidecar-url + camera_snapshot 캡처
- UiaPlayerHost.TryRestoreCamera, PlayerEngine 재생 전 복원
- 149 tests

LauncherUI (#15):
- Sidecar URL 체크박스 + 입력란 (녹화/재생 모두 연동)
- 재생 속도 슬라이더 (0.25x~4.0x, 기본 1.0x)
- 빌드 타임스탬프 타이틀바 표시
- 녹화 완료 후 RecordNameBox 초기화
- UiAnalysisWindow 추가

PlayerEngine (#15):
- CancellationToken 지원 (중단 버튼 동작)
- Focus 스텝 early return (no-op, issue #11)
- Type/Drag unresolvable UIA path fallback
- SpeedMultiplier 옵션

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

src/Sut/EgBim/Recordingtest.Sut.EgBim.PluginHost/BridgeHttpServer.cs

@@ -41,8 +41,20 @@ public sealed class BridgeHttpServer : IDisposable
             catch { return; }
             try
             {
-                var path = ctx.Request.Url?.AbsolutePath ?? "/";
-                var (status, body) = _router.Route(path);
+                var path   = ctx.Request.Url?.AbsolutePath ?? "/";
+                var method = ctx.Request.HttpMethod ?? "GET";
+                string requestBody = string.Empty;
+                if (ctx.Request.HasEntityBody)
+                {
+                    try
+                    {
+                        using var reader = new System.IO.StreamReader(
+                            ctx.Request.InputStream, Encoding.UTF8);
+                        requestBody = reader.ReadToEnd();
+                    }
+                    catch { /* ignore body read failures */ }
+                }
+                var (status, body) = _router.Route(method, path, requestBody);
                 var bytes = Encoding.UTF8.GetBytes(body);
                 ctx.Response.StatusCode = (int)status;
                 ctx.Response.ContentType = "application/json";

src/Sut/EgBim/Recordingtest.Sut.EgBim.PluginHost/ChainedEngineStateProvider.cs

@@ -48,6 +48,17 @@ public sealed class ChainedEngineStateProvider : IEngineStateProvider
 
     public bool GetRenderComplete() => _primary.GetRenderComplete();
 
+    /// <summary>
+    /// Camera writes go to the primary only (HmegDirectStateProvider).
+    /// The reflection fallback does not support writes; chaining writes would
+    /// risk applying a stale camera twice.
+    /// </summary>
+    public void SetCamera(CameraSnapshot snapshot)
+    {
+        try { _primary.SetCamera(snapshot); }
+        catch { /* never throw from sidecar thread */ }
+    }
+
     private static bool IsDefault(CameraSnapshot c) =>
         c.Eye is { Length: >= 3 } e && e[0] == 0 && e[1] == 0 && e[2] == 0 &&
         c.Target is { Length: >= 3 } t && t[0] == 0 && t[1] == 0 && t[2] == 0;

src/Sut/EgBim/Recordingtest.Sut.EgBim.PluginHost/HmEgBridgePlugin.cs

@@ -106,7 +106,18 @@ public sealed class HmEgBridgePlugin : EditorPlugin, IDisposable
             catch { return null; }
         };
 
-        var direct = new HmegDirectStateProvider(spaceProvider, viewportProvider, documentPathProvider);
+        // Dispatch camera writes onto the WPF UI thread so DependencyProperty
+        // setters on CameraCore are called from the correct thread.
+        Action<Action>? uiDispatch = null;
+        try
+        {
+            var dispatcher = System.Windows.Application.Current?.Dispatcher;
+            if (dispatcher is not null)
+                uiDispatch = action => dispatcher.Invoke(action);
+        }
+        catch { /* best-effort: leave null, SetCamera falls back to direct call */ }
+
+        var direct = new HmegDirectStateProvider(spaceProvider, viewportProvider, documentPathProvider, uiDispatch);
         var fallback = new ReflectionEngineStateProvider(this);
         return new ChainedEngineStateProvider(direct, fallback);
     }

src/Sut/EgBim/Recordingtest.Sut.EgBim.PluginHost/IEngineStateProvider.cs

@@ -80,4 +80,10 @@ public sealed class ReflectionEngineStateProvider : IEngineStateProvider
         // expose a stable "frame finished" flag we can poll without an event.
         return true;
     }
+
+    public void SetCamera(CameraSnapshot snapshot)
+    {
+        // Reflection fallback does not implement camera write; silently no-op.
+        // The primary HmegDirectStateProvider handles this in production.
+    }
 }

src/Sut/EgBim/Recordingtest.Sut.EgBim.PluginHost/StateRouter.cs

@@ -1,6 +1,7 @@
 using System.Globalization;
 using System.Net;
 using System.Text;
+using System.Text.Json;
 using Recordingtest.Bridge;
 
 namespace Recordingtest.Sut.EgBim.PluginHost;
@@ -20,12 +21,19 @@ public sealed class StateRouter
         _port = port;
     }
 
-    public (HttpStatusCode Status, string Body) Route(string path)
+    /// <summary>Backwards-compatible GET overload for unit tests.</summary>
+    public (HttpStatusCode Status, string Body) Route(string path) => Route("GET", path, "");
+
+    public (HttpStatusCode Status, string Body) Route(string method, string path, string body = "")
     {
         var p = (path ?? "/").TrimEnd('/');
         if (p.Length == 0) p = "/";
+        var m = (method ?? "GET").ToUpperInvariant();
         try
         {
+            if (m == "POST" && p == "/camera/restore")
+                return (HttpStatusCode.OK, RestoreCamera(body));
+
             return p switch
             {
                 "/health" => (HttpStatusCode.OK, $"{{\"status\":\"ok\",\"port\":{_port}}}"),
@@ -42,6 +50,34 @@ public sealed class StateRouter
         }
     }
 
+    private string RestoreCamera(string body)
+    {
+        try
+        {
+            using var doc = JsonDocument.Parse(body);
+            var r = doc.RootElement;
+            var eye    = ReadVecFromJson(r, "eye");
+            var target = ReadVecFromJson(r, "target");
+            var up     = ReadVecFromJson(r, "up");
+            double fov = r.TryGetProperty("fov", out var fovEl) ? fovEl.GetDouble() : 45.0;
+            _provider.SetCamera(new CameraSnapshot(eye, target, up, fov));
+            return "{\"ok\":true}";
+        }
+        catch (Exception ex)
+        {
+            return $"{{\"ok\":false,\"error\":{JsonString(ex.Message)}}}";
+        }
+    }
+
+    private static double[] ReadVecFromJson(JsonElement root, string key)
+    {
+        if (!root.TryGetProperty(key, out var arr)) return new double[3];
+        var result = new double[arr.GetArrayLength()];
+        int i = 0;
+        foreach (var e in arr.EnumerateArray()) result[i++] = e.GetDouble();
+        return result;
+    }
+
     private string BuildSelection()
     {
         var ids = _provider.GetSelectedIds();