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>

.gitignore

@@ -14,3 +14,17 @@ audit-*.md
 
 # Memory-dump artifacts captured by audit probes (hundreds of MB each)
 *.bin
+
+# Raw trace/query dumps under audit-runs/ (regenerable, multi-GB).
+# Keep the small .md/.txt/.json analysis notes; drop the heavy capture formats.
+*.jsonl
+*.jsonl.gz
+*.gz
+*.csv
+
+# Agent worktrees & local Claude state (huge; not source)
+.claude/
+
+# Local DB backups / scratch state
+*.bak
+exit-thread-state.json