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/review-a-step2-natural-trigger/extract_ours_tid1_full.py

@@ -0,0 +1,86 @@
+#!/usr/bin/env python3
+"""Extract ours tid=1 timeline, focused on the final wedge region.
+
+Ours wedges by ~1.7s, so we want the FINAL kernel-call sequence ours emits
+on tid=1 before the wait that wedges. Compare against canary tid=6 at a
+matching matched-prefix point.
+"""
+import json
+import os
+from collections import Counter
+
+INPUT = "/home/fabi/RE - Project Sylpheed/xenia-rs/audit-runs/phase-w-wedge-reattack/ours-postfix.jsonl"
+OUTDIR = os.path.dirname(os.path.abspath(__file__))
+TARGET_TID = 1
+
+kernel_calls = []
+kernel_returns = []
+handle_creates = []
+thread_events = []
+import_calls = []
+wait_events = []
+other = []
+
+last_idx = -1
+last_host_ns = 0
+with open(INPUT, "r") as f:
+    for line in f:
+        try:
+            ev = json.loads(line)
+        except json.JSONDecodeError:
+            continue
+        if ev.get("tid") != TARGET_TID:
+            continue
+        kind = ev.get("kind", "")
+        last_idx = ev.get("tid_event_idx", last_idx)
+        last_host_ns = ev.get("host_ns", last_host_ns)
+        if kind == "kernel.call":
+            kernel_calls.append(ev)
+        elif kind == "kernel.return":
+            kernel_returns.append(ev)
+        elif kind == "handle.create":
+            handle_creates.append(ev)
+        elif kind in ("thread.create", "thread.exit"):
+            thread_events.append(ev)
+        elif kind == "import.call":
+            import_calls.append(ev)
+        elif kind in ("wait.begin", "wait.end", "wait.wake"):
+            wait_events.append(ev)
+        else:
+            other.append(ev)
+
+print(f"Ours tid={TARGET_TID} total kernel.call: {len(kernel_calls)}")
+print(f"Ours tid={TARGET_TID} last tid_event_idx: {last_idx}")
+print(f"Ours tid={TARGET_TID} last host_ns: {last_host_ns} ({last_host_ns/1e9:.3f} s)")
+
+call_counts = Counter()
+for ev in kernel_calls:
+    call_counts[ev["payload"].get("name", "?")] += 1
+
+# Show LAST 100 events on tid=1 to identify the wedge approach.
+last_evts = []
+for ev in kernel_calls + kernel_returns + wait_events + handle_creates + thread_events:
+    last_evts.append((ev["host_ns"], ev["tid_event_idx"], ev["kind"], ev["payload"]))
+last_evts.sort()
+last_evts = last_evts[-150:]
+
+with open(os.path.join(OUTDIR, "ours-tid1-final-150.csv"), "w") as f:
+    f.write("host_ns,tid_event_idx,kind,name,detail\n")
+    for host_ns, idx, kind, payload in last_evts:
+        name = payload.get("name", "")
+        detail = json.dumps(payload)[:300].replace('"', '""')
+        f.write(f'{host_ns},{idx},{kind},{name},"{detail}"\n')
+
+with open(os.path.join(OUTDIR, "ours-tid1-summary"), "w") as f:
+    f.write(f"Ours tid={TARGET_TID} summary\n")
+    f.write(f"\nTotal kernel.call: {len(kernel_calls)}\n")
+    f.write(f"Last tid_event_idx: {last_idx}\n")
+    f.write(f"Last host_ns: {last_host_ns} ({last_host_ns/1e9:.3f} s)\n")
+    f.write(f"\n=== Top kernel.call by frequency ===\n")
+    for name, c in call_counts.most_common(80):
+        f.write(f"  {c:6d}  {name}\n")
+    f.write(f"\n=== Unique kernel.call names ===\n")
+    f.write(f"  {len(call_counts)}\n")
+
+print(f"Wrote ours-tid1-final-150.csv")
+print(f"Wrote ours-tid1-summary")