Fix smoke 2차 gaps: hotkey tests, focus filter, viewport picking (#13)

Gap E — Hotkey named key
- UiaPlayerHost: extract ParsedHotkey record + ParseHotkey static
- HotkeyParseTests: 8 tests (enter/tab/a/ctrl+c/ctrl+shift+s/f5/alt+f4/empty)

Gap F — recorder focus_change SUT filter
- FocusEventFilter.ShouldAccept static rule (same/zero/unknown/unknown-sut)
- Program.cs wires it inside RegisterFocusChangedEvent callback
- FocusEventFilterTests: 4 tests

Gap G — viewport picking foreign-process fallback
- IWindowPointSource + WindowPointResolver pure resolver
- FlaUiPointSource wired in Program.cs (best-effort hit test, honest partial for live SUT)
- WindowPointResolverTests: 5 tests

Tests: 77 → 94, build 0/0 (TreatWarningsAsErrors preserved).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

tests/Recordingtest.Player.Tests/HotkeyParseTests.cs

@@ -0,0 +1,71 @@
+using FlaUI.Core.WindowsAPI;
+using Xunit;
+
+namespace Recordingtest.Player.Tests;
+
+public class HotkeyParseTests
+{
+    [Fact]
+    public void Enter_NoMods_ReturnsReturnKey()
+    {
+        var p = UiaPlayerHost.ParseHotkey("enter");
+        Assert.Empty(p.Modifiers);
+        Assert.Equal(VirtualKeyShort.RETURN, p.Main);
+    }
+
+    [Fact]
+    public void Tab_NoMods_ReturnsTabKey()
+    {
+        var p = UiaPlayerHost.ParseHotkey("tab");
+        Assert.Empty(p.Modifiers);
+        Assert.Equal(VirtualKeyShort.TAB, p.Main);
+    }
+
+    [Fact]
+    public void SingleChar_a_ReturnsAKey()
+    {
+        var p = UiaPlayerHost.ParseHotkey("a");
+        Assert.Empty(p.Modifiers);
+        Assert.Equal((VirtualKeyShort)'A', p.Main);
+    }
+
+    [Fact]
+    public void CtrlC_ReturnsControlModPlusC()
+    {
+        var p = UiaPlayerHost.ParseHotkey("ctrl+c");
+        Assert.Equal(new[] { VirtualKeyShort.CONTROL }, p.Modifiers);
+        Assert.Equal((VirtualKeyShort)'C', p.Main);
+    }
+
+    [Fact]
+    public void CtrlShiftS_ReturnsBothModsPlusS()
+    {
+        var p = UiaPlayerHost.ParseHotkey("ctrl+shift+s");
+        Assert.Equal(new[] { VirtualKeyShort.CONTROL, VirtualKeyShort.SHIFT }, p.Modifiers);
+        Assert.Equal((VirtualKeyShort)'S', p.Main);
+    }
+
+    [Fact]
+    public void F5_ReturnsF5Key()
+    {
+        var p = UiaPlayerHost.ParseHotkey("f5");
+        Assert.Empty(p.Modifiers);
+        Assert.Equal((VirtualKeyShort)(0x70 + 4), p.Main);
+    }
+
+    [Fact]
+    public void AltF4_ReturnsAltPlusF4()
+    {
+        var p = UiaPlayerHost.ParseHotkey("alt+f4");
+        Assert.Equal(new[] { VirtualKeyShort.ALT }, p.Modifiers);
+        Assert.Equal((VirtualKeyShort)(0x70 + 3), p.Main);
+    }
+
+    [Fact]
+    public void Empty_ReturnsNoModsNoMain()
+    {
+        var p = UiaPlayerHost.ParseHotkey("");
+        Assert.Empty(p.Modifiers);
+        Assert.Null(p.Main);
+    }
+}