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-c23-scheduler-determinism-plan/probes/jitter_profile_c21.json

@@ -0,0 +1,153 @@
+profiling xenia-canary/build-cross/bin/Windows/Debug/canary-cold-c21.jsonl...
+{
+  "canary-cold-c21.jsonl": {
+    "path": "xenia-canary/build-cross/bin/Windows/Debug/canary-cold-c21.jsonl",
+    "tid6_total_seen": 120002,
+    "waitbegins_by_sid": {
+      "8ec49cc7eb991db6": 33,
+      "14afe71d37ff58a7": 31,
+      "a25a16a4f6f547aa": 28,
+      "2a70efeeed4f4fb6": 12,
+      "72a4170012353517": 10,
+      "7b3b3faec1388b19": 4,
+      "92b9c026e295e0e5": 3,
+      "df2b7bc3c60f41b9": 2,
+      "eec602f5f9aa4bac": 2,
+      "1938a086284cdbf1": 1
+    },
+    "rtlenter_calls": 19518,
+    "rtlleave_calls": 19517,
+    "window_events": [
+      {
+        "idx": 104595,
+        "kind": "import.call",
+        "name": "RtlLeaveCriticalSection"
+      },
+      {
+        "idx": 104596,
+        "kind": "kernel.call",
+        "name": "RtlLeaveCriticalSection"
+      },
+      {
+        "idx": 104597,
+        "kind": "kernel.return",
+        "name": "RtlLeaveCriticalSection"
+      },
+      {
+        "idx": 104598,
+        "kind": "import.call",
+        "name": "RtlEnterCriticalSection"
+      },
+      {
+        "idx": 104599,
+        "kind": "kernel.call",
+        "name": "RtlEnterCriticalSection"
+      },
+      {
+        "idx": 104600,
+        "kind": "kernel.return",
+        "name": "RtlEnterCriticalSection"
+      },
+      {
+        "idx": 104601,
+        "kind": "import.call",
+        "name": "RtlLeaveCriticalSection"
+      },
+      {
+        "idx": 104602,
+        "kind": "kernel.call",
+        "name": "RtlLeaveCriticalSection"
+      },
+      {
+        "idx": 104603,
+        "kind": "kernel.return",
+        "name": "RtlLeaveCriticalSection"
+      },
+      {
+        "idx": 104604,
+        "kind": "import.call",
+        "name": "RtlEnterCriticalSection"
+      },
+      {
+        "idx": 104605,
+        "kind": "kernel.call",
+        "name": "RtlEnterCriticalSection"
+      },
+      {
+        "idx": 104606,
+        "kind": "kernel.return",
+        "name": "RtlEnterCriticalSection"
+      },
+      {
+        "idx": 104607,
+        "kind": "import.call",
+        "name": "RtlEnterCriticalSection"
+      },
+      {
+        "idx": 104608,
+        "kind": "kernel.call",
+        "name": "RtlEnterCriticalSection"
+      },
+      {
+        "idx": 104609,
+        "kind": "kernel.return",
+        "name": "RtlEnterCriticalSection"
+      },
+      {
+        "idx": 104610,
+        "kind": "import.call",
+        "name": "RtlLeaveCriticalSection"
+      },
+      {
+        "idx": 104611,
+        "kind": "kernel.call",
+        "name": "RtlLeaveCriticalSection"
+      },
+      {
+        "idx": 104612,
+        "kind": "kernel.return",
+        "name": "RtlLeaveCriticalSection"
+      },
+      {
+        "idx": 104613,
+        "kind": "import.call",
+        "name": "RtlLeaveCriticalSection"
+      },
+      {
+        "idx": 104614,
+        "kind": "kernel.call",
+        "name": "RtlLeaveCriticalSection"
+      },
+      {
+        "idx": 104615,
+        "kind": "kernel.return",
+        "name": "RtlLeaveCriticalSection"
+      },
+      {
+        "idx": 104616,
+        "kind": "import.call",
+        "name": "NtClose"
+      },
+      {
+        "idx": 104617,
+        "kind": "kernel.call",
+        "name": "NtClose"
+      },
+      {
+        "idx": 104618,
+        "kind": "handle.destroy",
+        "name": ""
+      },
+      {
+        "idx": 104619,
+        "kind": "kernel.return",
+        "name": "NtClose"
+      },
+      {
+        "idx": 104620,
+        "kind": "import.call",
+        "name": "RtlEnterCriticalSection"
+      }
+    ]
+  }
+}