Enable Codex goals in provider templates (#3089)
* Enable Codex goals in provider templates
* feat: add Codex goal mode toggle
- Remove forced goals=true from Codex provider presets and custom templates.
- Add a Codex provider editor switch that updates [features].goals on demand.
- Update docs, i18n, and regression coverage for the optional Goal mode flow.
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Co-authored-by: Jason <farion1231@gmail.com>
Kairos Duan