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-c5-NtWriteFile/snap/ours/kernel.json

@@ -0,0 +1,62 @@
+{
+  "deterministic_skip": [
+    "raw_handle_id",
+    "exports_registered_count"
+  ],
+  "engine": "ours",
+  "exports_registered_count": 199,
+  "exports_registered_sample": [
+    "xam.xex!NetDll_WSACleanup",
+    "xam.xex!NetDll_WSAStartup",
+    "xam.xex!XGetAVPack",
+    "xam.xex!XGetGameRegion",
+    "xam.xex!XGetLanguage",
+    "xam.xex!XGetVideoMode",
+    "xam.xex!XMsgInProcessCall",
+    "xam.xex!XMsgStartIORequest",
+    "xam.xex!XMsgStartIORequestEx",
+    "xam.xex!XNotifyGetNext",
+    "xam.xex!XNotifyPositionUI",
+    "xam.xex!XamAlloc",
+    "xam.xex!XamContentClose",
+    "xam.xex!XamContentCreate",
+    "xam.xex!XamContentCreateEnumerator",
+    "xam.xex!XamContentDelete",
+    "xam.xex!XamContentGetCreator",
+    "xam.xex!XamContentGetDeviceData",
+    "xam.xex!XamContentGetDeviceName",
+    "xam.xex!XamContentGetDeviceState",
+    "xam.xex!XamContentSetThumbnail",
+    "xam.xex!XamEnableInactivityProcessing",
+    "xam.xex!XamEnumerate",
+    "xam.xex!XamFree",
+    "xam.xex!XamGetExecutionId",
+    "xam.xex!XamGetSystemVersion",
+    "xam.xex!XamInputGetCapabilities",
+    "xam.xex!XamInputGetKeystrokeEx",
+    "xam.xex!XamInputGetState",
+    "xam.xex!XamInputSetState",
+    "xam.xex!XamLoaderLaunchTitle",
+    "xam.xex!XamLoaderTerminateTitle"
+  ],
+  "exports_registered_sha256": "bb97815f82b2313c9eaa07bf80dab47c5c23408c24203a1283dfb2aba1e84e09",
+  "handle_name_table": [],
+  "notification_listeners": [],
+  "objects": [
+    {
+      "details": {
+        "entry_pc": "0x824ab748",
+        "exit_code": null,
+        "hw_id": 0,
+        "is_entry_thread": true,
+        "thread_id": 1
+      },
+      "handle_semantic_id": "9879c5053fedb1d0",
+      "name": null,
+      "raw_handle_id": "0x00001000",
+      "type": "Thread",
+      "type_code": 5
+    }
+  ],
+  "schema_version": 1
+}