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/phase-c12-NtQueryFullAttributesFile/diff-cold-vs-cold.md

@@ -0,0 +1,131 @@
+# Phase A diff report
+
+**This report is the output of Phase A's diff harness. Divergences
+shown here are INPUT for Phase B (first-divergence localization),
+not findings of Phase A.** Phase A's job is to make the harness
+itself correct, not to analyze what it surfaces.
+
+## Summary
+
+| canary_tid | ours_tid | matched | canary_total | ours_total | first_divergence_at |
+|---|---|---|---|---|---|
+| 4 | 11 | 9 | 20000 | 9 | — |
+| 6 | 1 | 103862 | 250000 | 108471 | 103862 |
+| 7 | 2 | 29 | 29 | 30 | — |
+| 12 | 7 | 2 | 10532 | 3 | 2 |
+| 14 | 9 | 39 | 20000 | 75 | 39 |
+| 15 | 10 | 15 | 20000 | 15 | — |
+
+## canary_tid=4 → ours_tid=11
+
+No divergence within the 9 compared events (canary has 20000, ours has 9).
+
+## canary_tid=6 → ours_tid=1
+
+First divergence at `tid_event_idx=103862`: payload.return_value: canary=18446744072635809844 ours=0
+
+**Pre-context (last 5 matching events):**
+```
+  canary: [103857] import.call RtlInitAnsiString
+  ours:   [103857] import.call RtlInitAnsiString
+  canary: [103858] kernel.call RtlInitAnsiString
+  ours:   [103858] kernel.call RtlInitAnsiString
+  canary: [103859] kernel.return RtlInitAnsiString
+  ours:   [103859] kernel.return RtlInitAnsiString
+  canary: [103860] import.call NtCreateFile
+  ours:   [103860] import.call NtCreateFile
+  canary: [103861] kernel.call NtCreateFile
+  ours:   [103861] kernel.call NtCreateFile
+```
+
+**Divergent event:**
+```
+  canary: [103862] kernel.return NtCreateFile
+  ours:   [103862] kernel.return NtCreateFile
+```
+
+**Next event after the divergence (if any):**
+```
+  canary: [103863] import.call RtlNtStatusToDosError
+  ours:   [103863] import.call RtlEnterCriticalSection
+```
+
+**Raw events (JSON):**
+```json
+{"deterministic": true, "engine": "canary", "guest_cycle": 0, "host_ns": 805501600, "kind": "kernel.return", "payload": {"name": "NtCreateFile", "return_value": 18446744072635809844, "side_effects": [], "status": "0xc0000034"}, "schema_version": 1, "tid": 6, "tid_event_idx": 103862}
+{"deterministic": true, "engine": "ours", "guest_cycle": 5470532, "host_ns": 463681670, "kind": "kernel.return", "payload": {"name": "NtCreateFile", "return_value": 0, "side_effects": [], "status": "0x00000000"}, "schema_version": 1, "tid": 1, "tid_event_idx": 103862}
+```
+
+## canary_tid=7 → ours_tid=2
+
+No divergence within the 29 compared events (canary has 29, ours has 30).
+
+## canary_tid=12 → ours_tid=7
+
+First divergence at `tid_event_idx=2`: payload.return_value: canary=258 ours=0
+
+**Pre-context (last 5 matching events):**
+```
+  canary: [0] import.call KeWaitForSingleObject
+  ours:   [0] import.call KeWaitForSingleObject
+  canary: [1] kernel.call KeWaitForSingleObject
+  ours:   [1] kernel.call KeWaitForSingleObject
+```
+
+**Divergent event:**
+```
+  canary: [2] kernel.return KeWaitForSingleObject
+  ours:   [2] kernel.return KeWaitForSingleObject
+```
+
+**Next event after the divergence (if any):**
+```
+  canary: [3] import.call RtlEnterCriticalSection
+  ours:   <end of stream>
+```
+
+**Raw events (JSON):**
+```json
+{"deterministic": true, "engine": "canary", "guest_cycle": 0, "host_ns": 935048400, "kind": "kernel.return", "payload": {"name": "KeWaitForSingleObject", "return_value": 258, "side_effects": [], "status": "0x00000102"}, "schema_version": 1, "tid": 12, "tid_event_idx": 2}
+{"deterministic": true, "engine": "ours", "guest_cycle": 30, "host_ns": 479443976, "kind": "kernel.return", "payload": {"name": "KeWaitForSingleObject", "return_value": 0, "side_effects": [], "status": "0x00000000"}, "schema_version": 1, "tid": 7, "tid_event_idx": 2}
+```
+
+## canary_tid=14 → ours_tid=9
+
+First divergence at `tid_event_idx=39`: payload.ord: canary=503 ours=293
+
+**Pre-context (last 5 matching events):**
+```
+  canary: [34] kernel.call KeReleaseSpinLockFromRaisedIrql
+  ours:   [34] kernel.call KeReleaseSpinLockFromRaisedIrql
+  canary: [35] kernel.return KeReleaseSpinLockFromRaisedIrql
+  ours:   [35] kernel.return KeReleaseSpinLockFromRaisedIrql
+  canary: [36] import.call KfLowerIrql
+  ours:   [36] import.call KfLowerIrql
+  canary: [37] kernel.call KfLowerIrql
+  ours:   [37] kernel.call KfLowerIrql
+  canary: [38] kernel.return KfLowerIrql
+  ours:   [38] kernel.return KfLowerIrql
+```
+
+**Divergent event:**
+```
+  canary: [39] import.call XAudioGetVoiceCategoryVolumeChangeMask
+  ours:   [39] import.call RtlEnterCriticalSection
+```
+
+**Next event after the divergence (if any):**
+```
+  canary: [40] kernel.call XAudioGetVoiceCategoryVolumeChangeMask
+  ours:   [40] kernel.call RtlEnterCriticalSection
+```
+
+**Raw events (JSON):**
+```json
+{"deterministic": true, "engine": "canary", "guest_cycle": 0, "host_ns": 1106484200, "kind": "import.call", "payload": {"module": "xboxkrnl.exe", "name": "XAudioGetVoiceCategoryVolumeChangeMask", "ord": 503}, "schema_version": 1, "tid": 14, "tid_event_idx": 39}
+{"deterministic": true, "engine": "ours", "guest_cycle": 417, "host_ns": 1658972624, "kind": "import.call", "payload": {"module": "xboxkrnl.exe", "name": "RtlEnterCriticalSection", "ord": 293}, "schema_version": 1, "tid": 9, "tid_event_idx": 39}
+```
+
+## canary_tid=15 → ours_tid=10
+
+No divergence within the 15 compared events (canary has 20000, ours has 15).