handoff: VSync/event-wedge fixes + iterate 2.A–2.BC research notes

Source changes (dormant parity infra, retained from iterate 2.AI/2.AO):
- xenia-kernel/exports.rs: nt_create_event manual_reset polarity +
  related event wiring
- xenia-gpu/mmio_region.rs: D1MODE_VBLANK_VLINE_STATUS hardcode parity

Also lands the audit-runs/ analysis notes (.md/.txt/.json digests) for the
iterate 2.x VSync/0x10e8/0x1004 wedge investigation. Raw trace dumps
(.jsonl/.gz/.csv/.stdout) and agent worktrees (.claude/) are gitignored as
regenerable local artifacts — see memory + HANDOFF for the running findings.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

audit-runs/iterate-2AZ-vsync-cadence/fin2-A.json

@@ -0,0 +1,10 @@
+{
+  "instructions": 500000010,
+  "imports": 21398305,
+  "unimpl": 0,
+  "draws": 0,
+  "swaps": 1,
+  "unique_render_targets": 0,
+  "shader_blobs_live": 0,
+  "texture_cache_entries": 0
+}