feat: queue-aware paper fills, kill switch, systemd services, WQI+FundingArb in paper trader

- live/paper_trader.py: replaced random 5% fill probability in simulate_avellaneda()
  with QueueAwareFillModel — fills only when aggressor volume exceeds depth ahead,
  regime-adaptive quote placement (tight in LOW_VOL, wide in HIGH_VOL). Integrated
  WQI Predictor and Funding Rate Arb as new strategies with signal generation.
  Dashboard metrics now include WQI summaries, funding arb status, and fill model
  throughput stats (fill rate, fills vs skips). 14 strategies total.
- scripts/kill_switch.py: emergency kill switch — flattens all positions, cancels
  all open orders, verifies account is flat. Supports --dry-run, --mainnet, retry
  logic, L1 action signing. Reads private key from HL_PRIVATE_KEY env or ~/.hl/key.
- infrastructure/systemd/: three service unit files for production deployment:
  ftdt-collector (data collection), ftdt-paper (trading node v2), ftdt-dashboard
  (FastAPI backend). Includes memory/cpu limits, auto-restart, log rotation.

321 tests passing.

infrastructure/systemd/ftdt-collector.service

@@ -0,0 +1,26 @@
+# FTDT Quant Lab — Data Collector
+# Install: sudo cp ftdt-collector.service /etc/systemd/system/
+#          sudo systemctl enable ftdt-collector
+#          sudo systemctl start ftdt-collector
+
+[Unit]
+Description=FTDT Quant Lab — Hyperliquid Data Collector
+After=network-online.target
+Wants=network-online.target
+
+[Service]
+Type=simple
+User=satoshi
+WorkingDirectory=/home/satoshi/ftdt-quant-lab
+Environment=PYTHONUNBUFFERED=1
+Environment=PATH=/home/satoshi/ftdt-quant-lab/.venv/bin:/usr/local/bin:/usr/bin:/bin
+ExecStart=/home/satoshi/ftdt-quant-lab/.venv/bin/python -m cli collect --mainnet --coins BTC,ETH,SOL,HYPE --data-dir data/raw --poll-interval 60 --flush-interval 5
+Restart=always
+RestartSec=10
+StandardOutput=append:/home/satoshi/ftdt-quant-lab/logs/collector.log
+StandardError=append:/home/satoshi/ftdt-quant-lab/logs/collector.log
+MemoryMax=512M
+CPUQuota=50%
+
+[Install]
+WantedBy=multi-user.target

infrastructure/systemd/ftdt-dashboard.service

@@ -0,0 +1,26 @@
+# FTDT Quant Lab — Dashboard Server
+# Install: sudo cp ftdt-dashboard.service /etc/systemd/system/
+#          sudo systemctl enable ftdt-dashboard
+#          sudo systemctl start ftdt-dashboard
+
+[Unit]
+Description=FTDT Quant Lab — FastAPI Dashboard Backend
+After=network-online.target
+Wants=network-online.target
+
+[Service]
+Type=simple
+User=satoshi
+WorkingDirectory=/home/satoshi/ftdt-quant-lab
+Environment=PYTHONUNBUFFERED=1
+Environment=PATH=/home/satoshi/ftdt-quant-lab/.venv/bin:/usr/local/bin:/usr/bin:/bin
+ExecStart=/home/satoshi/ftdt-quant-lab/.venv/bin/python dashboard/server.py --port 9175
+Restart=always
+RestartSec=5
+StandardOutput=append:/home/satoshi/ftdt-quant-lab/logs/dashboard.log
+StandardError=append:/home/satoshi/ftdt-quant-lab/logs/dashboard.log
+MemoryMax=256M
+CPUQuota=25%
+
+[Install]
+WantedBy=multi-user.target

infrastructure/systemd/ftdt-paper.service

@@ -0,0 +1,27 @@
+# FTDT Quant Lab — Paper Trading Node
+# Install: sudo cp ftdt-paper.service /etc/systemd/system/
+#          sudo systemctl enable ftdt-paper
+#          sudo systemctl start ftdt-paper
+
+[Unit]
+Description=FTDT Quant Lab — Paper Trading Node (v2)
+After=network-online.target ftdt-collector.service
+Wants=network-online.target
+Requires=ftdt-collector.service
+
+[Service]
+Type=simple
+User=satoshi
+WorkingDirectory=/home/satoshi/ftdt-quant-lab
+Environment=PYTHONUNBUFFERED=1
+Environment=PATH=/home/satoshi/ftdt-quant-lab/.venv/bin:/usr/local/bin:/usr/bin:/bin
+ExecStart=/home/satoshi/ftdt-quant-lab/.venv/bin/python -m live.node_v2 --testnet --coins BTC,ETH --mode paper --equity 100000 --metrics-file /tmp/ftdt-metrics-v2.json
+Restart=always
+RestartSec=15
+StandardOutput=append:/home/satoshi/ftdt-quant-lab/logs/paper-node.log
+StandardError=append:/home/satoshi/ftdt-quant-lab/logs/paper-node.log
+MemoryMax=512M
+CPUQuota=50%
+
+[Install]
+WantedBy=multi-user.target