Complete installation and setup guide for OpenClaw, the personal AI assistant. Use this skill when the user wants to install OpenClaw, set up the gateway, configure channels (WhatsApp, Telegram, Slack, Discord, Signal, iMessage), troubleshoot installation issues, update OpenClaw, or understand the system architecture. Also triggers for queries about Clawdbot, Moltbot (previous names), skills management, or ClawdHub registry.