feat(codex): convert 4 workflow commands to Codex prompt format with serial execution

Convert parallel multi-agent/multi-CLI workflows to Codex-compatible serial execution:

- brainstorm-with-file: Parallel Creative/Pragmatic/Systematic perspectives → Serial CLI execution
- analyze-with-file: cli-explore-agent + parallel CLI → Native tools (Glob/Grep/Read) + serial Gemini CLI
- collaborative-plan-with-file: Parallel sub-agents → Serial domain planning loop
- unified-execute-with-file: DAG-based parallel wave execution → Serial task-by-task execution

Key Technical Changes:
- YAML header: Remove 'name' and 'allowed-tools' fields
- Variables: $ARGUMENTS → $TOPIC/$TASK/$PLAN
- Task agents: Task() calls → ccw cli commands with --tool flag
- Parallel execution: Parallel Task/Bash calls → Sequential loops
- Session format: Match existing Codex prompt structure

Pattern: For multi-step workflows, use explicit wait points with "⏳ Wait for completion before proceeding"

Author: catlog22