Release the operator cursor for cursor-clipping games

Games that ClipCursor / re-center via SetCursorPos while focused trap the operator's
mouse (the focus spoof makes them think they're always focused), so the operator
can't reach the overlay. The Focus subsystem now inline-hooks ClipCursor and
SetCursorPos (stdcall trampolines): while "release" is requested it forces
ClipCursor(NULL) and swallows the re-centering SetCursorPos; otherwise it passes them
through. It frees any existing clip at install and re-frees each worker tick (covers
one-time clippers and a runtime clip->release toggle).

Host: protocol v10->v11 adds HookControl::allow_cursor_clip (0 = release, the
default). The Injection panel gets a "Release operator cursor" checkbox and an F2
hotkey (InjectionPanel::toggle_cursor_release); default released, since the guest
plays via the pad so the game's clip is operator-only.

Verified: full build x64 + x86 clean; ctest x64 9/9, x86 3/3. The cursor behavior
against a real clipping game (Trails through Daybreak) needs a live injected session
to confirm; logic reviewed.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

hook/src/focus_spoof.hpp

@@ -20,6 +20,11 @@ bool install_focus_spoof(IpcClient& ipc);
 // to call each tick.
 void update_input_diagnostics(IpcClient& ipc);
 
+// While the focus subsystem is installed, free the operator's mouse each tick if the
+// host requested cursor release (covers games that ClipCursor once rather than every
+// frame, and a runtime toggle from clip -> release). No-op when clipping is allowed.
+void release_cursor_tick();
+
 // Restores the original window procedure and removes the focus API hooks.
 void remove_focus_spoof();