feat(benchmarks): static PTQ int8 (calibrated) results + overnight capture script

Conv-only static QDQ beats dynamic int8 on accuracy (PCK@20 96.61-96.63%
vs 96.52%, MPJPE +10% vs +18% over fp32) at ~equal size/latency; all-ops
QDQ strictly worse (int8 activations through attention glue). Entropy
calibration verified bit-identical to MinMax on this data. Deployment:
ONNX fp32 for speed (3.2ms), static conv-only QDQ for smallest (2.53MB).

Also: scripts/overnight-empty-capture.py — segmented UDP CSI recorder for
empty-room baselines (no glob collisions, detach-safe).

Co-Authored-By: claude-flow <ruv@ruv.net>

scripts/overnight-empty-capture.py

@@ -0,0 +1,80 @@
+#!/usr/bin/env python3
+"""Segmented overnight empty-room CSI capture (ADR-135 baseline / MAE corpus).
+
+Binds UDP once and writes fixed-duration JSONL segments with explicit names —
+no post-hoc renaming, no glob collisions with other recordings.
+
+Usage:
+    python scripts/overnight-empty-capture.py --segments 8 --segment-seconds 3300
+"""
+
+import argparse
+import json
+import os
+import socket
+import struct
+import time
+
+
+def parse_csi_packet(data):
+    """ADR-018 binary CSI packet → dict (same layout as record-csi-udp.py)."""
+    if len(data) < 8:
+        return None
+    node_id = data[4]
+    rssi = struct.unpack("b", bytes([data[6]]))[0]
+    channel = data[7]
+    iq = data[8:]
+    amplitudes = []
+    for i in range(0, len(iq) - 1, 2):
+        I = struct.unpack("b", bytes([iq[i]]))[0]
+        Q = struct.unpack("b", bytes([iq[i + 1]]))[0]
+        amplitudes.append(round((I * I + Q * Q) ** 0.5, 2))
+    return {
+        "type": "raw_csi",
+        "ts_ns": time.time_ns(),
+        "node_id": node_id,
+        "rssi": rssi,
+        "channel": channel,
+        "subcarriers": len(iq) // 2,
+        "amplitudes": amplitudes,
+        "iq_hex": iq.hex(),
+    }
+
+
+def main():
+    ap = argparse.ArgumentParser()
+    ap.add_argument("--port", type=int, default=5005)
+    ap.add_argument("--segments", type=int, default=8)
+    ap.add_argument("--segment-seconds", type=int, default=3300)
+    ap.add_argument("--output", default="data/recordings")
+    ap.add_argument("--prefix", default="overnight-empty")
+    args = ap.parse_args()
+
+    os.makedirs(args.output, exist_ok=True)
+    sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+    sock.bind(("0.0.0.0", args.port))
+    sock.settimeout(2.0)
+
+    for seg in range(1, args.segments + 1):
+        path = os.path.join(
+            args.output, f"{args.prefix}-seg{seg}-{int(time.time())}.csi.jsonl"
+        )
+        n = 0
+        t_end = time.time() + args.segment_seconds
+        with open(path, "w", encoding="utf-8") as f:
+            while time.time() < t_end:
+                try:
+                    data, _ = sock.recvfrom(4096)
+                except socket.timeout:
+                    continue
+                rec = parse_csi_packet(data)
+                if rec is not None:
+                    f.write(json.dumps(rec) + "\n")
+                    n += 1
+        print(f"segment {seg}: {n} frames -> {path}", flush=True)
+
+    print("capture complete", flush=True)
+
+
+if __name__ == "__main__":
+    main()