[codex] feat(design): add design inspiration workflow for uiux generation

[staruhub]

Summary

• add super-dev design list / recommend / apply for DESIGN.md-inspired design exploration
• persist the selected design inspiration into project config and regenerate uiux.md / ui-contract.json
• fix related config, prompt-template path, and doctor test isolation issues so the CLI flow stays clean

Why

Super Dev already had strong internal UI truth sources in output/*-uiux.md and output/*-ui-contract.json, but it lacked a lightweight inspiration layer for users who want to start from recognizable product aesthetics like Vercel, Linear, or Stripe. This change adds that inspiration workflow without introducing a second design source of truth.

What changed

• added curated design inspiration listing and recommendation in the existing design command group
• added design apply <slug> to store design_inspiration_slug and write output/*-design-inspiration.json
• wired explicit inspiration choice into DocumentGenerator, UI intelligence selection, UI/UX document output, and UI contract generation
• fixed config loading so minimal super-dev.yaml files do not emit false schema warnings
• fixed prompt template path resolution so CLI usage does not depend on current working directory layout
• isolated doctor --repair Codex tests from the real HOME directory

User impact

• users can browse built-in design inspirations
• users can get recommendations from current project context
• users can apply a chosen inspiration and immediately regenerate the project's UI documents and contract
• Super Dev still keeps uiux.md + ui-contract.json as the internal source of truth

Validation

• python3 -m pytest tests/unit/test_prompt_templates.py tests/unit/test_config.py tests/unit/test_requirement_parser.py tests/unit/test_ui_intelligence.py tests/integration/test_cli.py tests/integration/test_web_api.py -q
• result: 419 passed
• manual smoke validated design list, design recommend, and design apply vercel
• API health check after restart: http://127.0.0.1:8001/api/health -> {"status":"healthy","version":"2.3.7"}

Notes

• this PR is intentionally opened as a draft
• the change keeps the existing UI review and quality gate model intact rather than replacing it with raw external DESIGN.md files