feat: standardize request_user_input schema across all codex skills and add config reminder

- Update all 68 .codex/skills files to use correct request_user_input schema
  (header, id, question, options with label/description)
- Remove deprecated multiSelect, type, value, prompt fields
- Add mandatory confirmation gates to planning-only skills
- Add Codex config.toml reminder to ccw install CLI
- Add Codex configuration section to README.md and README_CN.md

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

README.md

@@ -87,6 +87,19 @@ npm install -g claude-code-workflow
 ccw install -m Global
 ```
 
+### Codex Configuration (Required for `.codex/skills/`)
+
+If you use **Codex CLI** with the `.codex/skills/` workflow skills, add these required features to your `~/.codex/config.toml`:
+
+```toml
+[features]
+default_mode_request_user_input = true   # Enable request_user_input tool for interactive confirmations
+multi_agent = true                       # Enable multi-agent coordination (spawn_agent, wait, etc.)
+enable_fanout = true                     # Enable spawn_agents_on_csv for parallel wave execution
+```
+
+> These features are required for workflow skills to function properly. Without them, interactive confirmation gates (`request_user_input`), subagent orchestration, and CSV-driven parallel execution will not work.
+
 ### Workflow Skills vs Commands
 
 CCW uses two types of invocations: