- Rename handler type strings: codergen → agent_loop, wait.human → human,
script → command, wait.timer → wait
- Rename handler modules/structs to match: AgentHandler, HumanHandler,
CommandHandler, WaitHandler
- Split one_shot into PromptHandler (handler/prompt.rs) with shape=tab mapping
- Remove CodergenMode enum and codergen_mode attribute — one_shot is now its
own handler type, not a mode flag on the agent loop handler
- Update all demo DOT files: codergen_mode="one_shot" → shape=tab
- Update spec, README, validation rules, preamble, and hook tests
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>