feat: add host-chat.sh — one-command server setup with friend instructions

Detects all available IPs (Tailscale, LAN, public), prints connect
command for friends to copy, prompts for password securely via getpass.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

lab/host-chat.sh

@@ -0,0 +1,96 @@
+#!/usr/bin/env bash
+#
+# host-chat.sh — Start cmd-chat server for remote friends
+#
+# Usage:
+#   ./lab/host-chat.sh                  # TLS on port 4000, prompts for password
+#   ./lab/host-chat.sh --port 5000      # Custom port
+#   ./lab/host-chat.sh --no-tls         # Disable TLS (not recommended)
+#
+# After starting, give your friend:
+#   python3 cmd_chat.py connect YOUR_IP PORT theirname --insecure
+#
+
+set -euo pipefail
+
+PORT="${1:-4000}"
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+PROJECT_ROOT="$(cd "$SCRIPT_DIR/.." && pwd)"
+NO_TLS=false
+
+# Parse args
+while [[ $# -gt 0 ]]; do
+    case "$1" in
+        --port)   PORT="$2"; shift 2 ;;
+        --no-tls) NO_TLS=true; shift ;;
+        *)        shift ;;
+    esac
+done
+
+cd "$PROJECT_ROOT"
+
+# Check deps
+echo "Checking dependencies..."
+for pkg in sanic srp cryptography websockets rich requests; do
+    if ! python3 -c "import $pkg" 2>/dev/null; then
+        echo "Installing missing dependencies..."
+        python3 -m pip install -r requirements.txt --quiet 2>/dev/null
+        break
+    fi
+done
+
+# Get all IPs for display
+echo ""
+echo "========================================="
+echo "  cmd-chat Server Setup"
+echo "========================================="
+echo ""
+echo "Your IP addresses:"
+
+# Tailscale IP
+TS_IP=$(tailscale ip -4 2>/dev/null || true)
+if [[ -n "$TS_IP" ]]; then
+    echo "  Tailscale:  $TS_IP  (recommended — encrypted tunnel)"
+fi
+
+# LAN IPs
+for iface in $(ip -4 -o addr show scope global 2>/dev/null | awk '{print $2}' | sort -u); do
+    IP=$(ip -4 -o addr show "$iface" 2>/dev/null | awk '{print $4}' | cut -d/ -f1)
+    echo "  $iface:  $IP"
+done
+
+# Public IP
+PUB_IP=$(curl -sf --max-time 3 ifconfig.me 2>/dev/null || true)
+if [[ -n "$PUB_IP" ]]; then
+    echo "  Public:     $PUB_IP  (requires port forwarding)"
+fi
+
+echo ""
+echo "========================================="
+
+# TLS flags
+SERVER_FLAGS=""
+PROTO="https"
+CLIENT_FLAG="--insecure"
+if $NO_TLS; then
+    SERVER_FLAGS="--no-tls"
+    PROTO="http"
+    CLIENT_FLAG="--no-tls"
+fi
+
+# Pick best IP for friend instructions
+BEST_IP="${TS_IP:-$(ip -4 -o addr show scope global 2>/dev/null | head -1 | awk '{print $4}' | cut -d/ -f1)}"
+
+echo ""
+echo "Tell your friend to run:"
+echo ""
+echo "  git clone https://github.com/leetcrypt/cmd-chat.git"
+echo "  cd cmd-chat && pip install -r requirements.txt"
+echo "  python3 cmd_chat.py connect $BEST_IP $PORT THEIR_NAME $CLIENT_FLAG"
+echo ""
+echo "They'll be prompted for the password (same one you're about to set)."
+echo "========================================="
+echo ""
+
+# Start server — password will be prompted by cmd_chat
+exec python3 cmd_chat.py serve 0.0.0.0 "$PORT" $SERVER_FLAGS