chore: Second cleanup wave - organize root directory

- Archive: 85 agent .txt files → docs/archive/agents/legacy_txt/
- Scripts: Move 110 shell scripts → scripts/ (keep deploy.sh in root)
- Models: Move 18 .safetensors → ml/models/checkpoints/training_artifacts/
- Delete: 34 directories (~33GB freed) - target/, coverage_*, test artifacts
- Build: Clean 14 build artifacts (.rlib, .o, .pid, binaries)
- Tests: Move 14 .rs files → tests/standalone/
- SQL: Move 5 files → sql/ (keep init-db*.sql for Docker)
- Wave 153: Archive to docs/archive/historical/wave153/
- Docs: Archive 9 markdown files to wave_d/reports/ and historical/

Total impact: ~34GB freed (both waves), root directory cleaned from 583 to ~40 essential files
Directory count reduced from 65 to 31 (52% reduction)
All historical data preserved in organized archive structure

scripts/setup_lld.sh

@@ -0,0 +1,133 @@
+#!/bin/bash
+set -e
+
+echo "=========================================="
+echo "LLD Linker Setup Script for Foxhunt"
+echo "=========================================="
+echo ""
+
+# Check if running with sudo
+if [ "$EUID" -eq 0 ]; then 
+    echo "✓ Running with sudo privileges"
+else
+    echo "⚠️  This script requires sudo privileges"
+    echo "   Please run: sudo bash $0"
+    exit 1
+fi
+
+# Install lld
+echo "Step 1: Installing lld..."
+apt-get update -qq
+apt-get install -y lld
+
+echo ""
+echo "Step 2: Verifying installation..."
+if command -v ld.lld &> /dev/null; then
+    echo "✓ LLD installed successfully"
+    ld.lld --version
+else
+    echo "✗ LLD installation failed"
+    exit 1
+fi
+
+# Update .cargo/config.toml
+echo ""
+echo "Step 3: Updating .cargo/config.toml..."
+FOXHUNT_DIR="/home/jgrusewski/Work/foxhunt"
+CONFIG_FILE="$FOXHUNT_DIR/.cargo/config.toml"
+
+if [ ! -f "$CONFIG_FILE" ]; then
+    echo "✗ Config file not found: $CONFIG_FILE"
+    exit 1
+fi
+
+# Backup original
+cp "$CONFIG_FILE" "$CONFIG_FILE.backup.$(date +%Y%m%d_%H%M%S)"
+echo "✓ Backup created: $CONFIG_FILE.backup.*"
+
+# Apply changes
+cat > "$CONFIG_FILE" << 'CONFIGEOF'
+[env]
+# SQLx offline mode - use cached query metadata from .sqlx/ directory
+# Generated with: cargo sqlx prepare --workspace
+SQLX_OFFLINE = "true"
+
+[build]
+rustflags = [
+    "-D", "unsafe_op_in_unsafe_fn",
+    "-D", "clippy::undocumented_unsafe_blocks",
+    "-W", "rust_2024_idioms",
+    "-C", "force-frame-pointers=yes",
+    # REMOVED: "-C", "stack-protector=strong",  # Not compatible with coverage tools
+    "-C", "relocation-model=pic",
+]
+
+[target.x86_64-unknown-linux-gnu]
+linker = "clang"
+rustflags = [
+    "-C", "link-arg=-Wl,-z,relro,-z,now",
+    "-C", "link-arg=-Wl,--as-needed",
+    "-C", "link-arg=-fuse-ld=lld",  # LLD linker for faster linking (5-10x improvement)
+    # CRITICAL HFT PERFORMANCE FLAGS - FIXES SIMD 10,000x REGRESSION
+    "-C", "target-cpu=native",
+    "-C", "target-feature=+avx2,+fma,+bmi2",
+    "-C", "opt-level=3",
+    "-C", "codegen-units=1",
+]
+
+# Profile-specific optimizations for maximum SIMD performance
+[profile.release]
+opt-level = 3
+lto = "fat"
+codegen-units = 1
+panic = "abort"
+strip = false
+debug = false
+overflow-checks = false
+
+# Benchmarking profile with SIMD optimizations
+[profile.bench]
+inherits = "release"
+debug = false
+
+# HFT-specific profile for production with aggressive SIMD optimization
+[profile.hft]
+inherits = "release"
+opt-level = 3
+lto = "fat"
+codegen-units = 1
+panic = "abort"
+strip = false
+overflow-checks = false
+CONFIGEOF
+
+echo "✓ Configuration updated"
+
+# Test compilation
+echo ""
+echo "Step 4: Testing compilation..."
+cd "$FOXHUNT_DIR"
+sudo -u jgrusewski bash << 'TESTEOF'
+cd /home/jgrusewski/Work/foxhunt
+echo "Running: cargo check --workspace"
+cargo check --workspace 2>&1 | head -20
+TESTEOF
+
+if [ $? -eq 0 ]; then
+    echo "✓ Compilation test passed"
+else
+    echo "⚠️  Compilation test encountered issues (this may be normal)"
+fi
+
+echo ""
+echo "=========================================="
+echo "✓ LLD Setup Complete!"
+echo "=========================================="
+echo ""
+echo "Next steps:"
+echo "1. Run a clean build: cargo clean && time cargo build --release"
+echo "2. Compare build times with previous builds"
+echo "3. Expected improvement: 40-60% faster linking"
+echo ""
+echo "Backup location: $CONFIG_FILE.backup.*"
+