Implements the desire-path from bd-dcahx: agents naturally try
'gt cat <bead-id>' to view bead content, following Unix conventions.
The command validates bead ID prefixes (bd-*, hq-*, mol-*) and
delegates to 'bd show' for the actual display.
Supports --json flag for programmatic use.
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
