feat: add setup skill with scripted steps (#258)

Replace inline SKILL.md instructions with executable shell scripts
for each setup phase (environment check, deps, container, auth,
groups, channels, mounts, service, verify). Scripts emit structured
status blocks for reliable parsing.

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

.claude/skills/setup/scripts/01-check-environment.sh

@@ -0,0 +1,108 @@
+#!/bin/bash
+set -euo pipefail
+
+# 01-check-environment.sh — Detect OS, Node, container runtimes, existing config
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+PROJECT_ROOT="$(cd "$SCRIPT_DIR/../../../.." && pwd)"
+LOG_FILE="$PROJECT_ROOT/logs/setup.log"
+
+mkdir -p "$PROJECT_ROOT/logs"
+
+log() { echo "[$(date '+%Y-%m-%d %H:%M:%S')] [check-environment] $*" >> "$LOG_FILE"; }
+
+log "Starting environment check"
+
+# Detect platform
+UNAME=$(uname -s)
+case "$UNAME" in
+  Darwin*) PLATFORM="macos" ;;
+  Linux*)  PLATFORM="linux" ;;
+  *)       PLATFORM="unknown" ;;
+esac
+log "Platform: $PLATFORM ($UNAME)"
+
+# Check Node
+NODE_OK="false"
+NODE_VERSION="not_found"
+if command -v node >/dev/null 2>&1; then
+  NODE_VERSION=$(node --version 2>/dev/null | sed 's/^v//')
+  MAJOR=$(echo "$NODE_VERSION" | cut -d. -f1)
+  if [ "$MAJOR" -ge 20 ] 2>/dev/null; then
+    NODE_OK="true"
+  fi
+  log "Node $NODE_VERSION found (major=$MAJOR, ok=$NODE_OK)"
+else
+  log "Node not found"
+fi
+
+# Check Apple Container
+APPLE_CONTAINER="not_found"
+if command -v container >/dev/null 2>&1; then
+  APPLE_CONTAINER="installed"
+  log "Apple Container: installed ($(which container))"
+else
+  log "Apple Container: not found"
+fi
+
+# Check Docker
+DOCKER="not_found"
+if command -v docker >/dev/null 2>&1; then
+  if docker info >/dev/null 2>&1; then
+    DOCKER="running"
+    log "Docker: running"
+  else
+    DOCKER="installed_not_running"
+    log "Docker: installed but not running"
+  fi
+else
+  log "Docker: not found"
+fi
+
+# Check existing config
+HAS_ENV="false"
+if [ -f "$PROJECT_ROOT/.env" ]; then
+  HAS_ENV="true"
+  log ".env file found"
+fi
+
+HAS_AUTH="false"
+if [ -d "$PROJECT_ROOT/store/auth" ] && [ "$(ls -A "$PROJECT_ROOT/store/auth" 2>/dev/null)" ]; then
+  HAS_AUTH="true"
+  log "WhatsApp auth credentials found"
+fi
+
+HAS_REGISTERED_GROUPS="false"
+if [ -f "$PROJECT_ROOT/data/registered_groups.json" ]; then
+  HAS_REGISTERED_GROUPS="true"
+  log "Registered groups config found (JSON)"
+elif [ -f "$PROJECT_ROOT/store/messages.db" ]; then
+  RG_COUNT=$(sqlite3 "$PROJECT_ROOT/store/messages.db" "SELECT COUNT(*) FROM registered_groups" 2>/dev/null || echo "0")
+  if [ "$RG_COUNT" -gt 0 ] 2>/dev/null; then
+    HAS_REGISTERED_GROUPS="true"
+    log "Registered groups found in database ($RG_COUNT)"
+  fi
+fi
+
+log "Environment check complete"
+
+# Output structured status block
+cat <<EOF
+=== NANOCLAW SETUP: CHECK_ENVIRONMENT ===
+PLATFORM: $PLATFORM
+NODE_VERSION: $NODE_VERSION
+NODE_OK: $NODE_OK
+APPLE_CONTAINER: $APPLE_CONTAINER
+DOCKER: $DOCKER
+HAS_ENV: $HAS_ENV
+HAS_AUTH: $HAS_AUTH
+HAS_REGISTERED_GROUPS: $HAS_REGISTERED_GROUPS
+STATUS: success
+LOG: logs/setup.log
+=== END ===
+EOF
+
+# Exit 2 if Node is missing or too old
+if [ "$NODE_OK" = "false" ]; then
+  exit 2
+fi