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>

src/Recordingtest.Player/Recordingtest.Player.csproj

@@ -12,4 +12,7 @@
     <PackageReference Include="FlaUI.UIA3" Version="4.0.0" />
     <PackageReference Include="YamlDotNet" Version="16.1.3" />
   </ItemGroup>
+  <ItemGroup>
+    <InternalsVisibleTo Include="Recordingtest.Player.Tests" />
+  </ItemGroup>
 </Project>