Replay each VR eye in one render pass

- Added eye_pass_plan.hpp: an eye keeps drawing in the render pass it has open across the frame's
  GX copies (only the mono render performs them), skips passes a later clear of the whole color and
  depth erases, and splits only for a clear of color alone or depth alone.
- render_stereo_eye follows that plan; the cockpit fallback is drawn inside the last pass instead of
  a render pass of its own that loaded the eye back.
- The stencil is now cleared where the eye actually starts, so a cockpit mask drawn in an erased pass
  can no longer punch holes in the HUD.
- [vr] single_pass_eyes (default on, live from F10) and debug.wiicompiled.eye_passes 0/1 on the Quest
  switch back to one render pass per recorded pass for A/B timing.
- Each new plan shape is logged once ("Eye replay plan: ...").
- Tests: EyePassPlan cases in gx_fifo_tests; stereo_multiplayer_smoke and stereo_frame_worker_smoke
  pass on D3D12.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

aurora-main/lib/aurora.cpp

@@ -2857,6 +2857,8 @@ void aurora_set_stereo_stop_at_display_copy(bool enabled) { aurora::gfx::set_ste
 bool aurora_get_stereo_stop_at_display_copy() { return aurora::gfx::get_stereo_stop_at_display_copy(); }
 void aurora_set_stereo_skip_copy_clears(bool enabled) { aurora::gfx::set_stereo_skip_copy_clears(enabled); }
 bool aurora_get_stereo_skip_copy_clears() { return aurora::gfx::get_stereo_skip_copy_clears(); }
+void aurora_set_stereo_single_pass_eyes(bool enabled) { aurora::gfx::set_stereo_single_pass_eyes(enabled); }
+bool aurora_get_stereo_single_pass_eyes() { return aurora::gfx::get_stereo_single_pass_eyes(); }
 void aurora_set_stereo_hud_screen(bool enabled, float width, float distance) {
   aurora::gfx::set_stereo_hud_screen(enabled, width, distance);
 }