Enable Gas Town to operate without tmux by using beads for args transport:
- Add `attached_args` field to beads AttachmentFields
- gt sling: Store args in bead description, graceful fallback if no tmux
- gt prime: Display attached args prominently on startup
- gt mol status: Include attached_args in status output
- gt spawn --naked: Assign work via mail only, skip tmux session
Agents discover args via gt prime / bd show when starting manually.
Docs added explaining what works vs degraded behavior in no-tmux mode.
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Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>