Plugin install from SSH remote session:
Plugin install from SSH remote session: manual cache copy required. claude plugins install fails with cannot be launched inside another Claude Code session (CLAUDECODE env var set). Manual install: (1) copy to ~/.claude/plugins/cache/claude-plugins-official/name/version/, (2) add to ~/.claude/plugins/installed_plugins.json, (3) add to settings.json enabledPlugins. Ensure .claude-plugin/plugin.json manifest exists. Plugins load at session start — new installs take effect next session.