Remove update_plan dependency from agent workflows

[shinpr]

Summary

• replace explicit update_plan requirements in 25 custom agent prompts with execution-discipline guidance
• preserve strict ordered execution for the reviewee-judgment resolution method
• restore per-step result verification and explain why avoiding early convergence matters
• bump the package patch version to 1.3.3

Rationale

Codex now defaults update_plan to disabled. This removes the unavailable tool dependency without adding replacement state or workflow machinery, while retaining direct guidance to follow required procedures through verification.

Testing

• npm run check:skills-index
• npm test
• git diff --check