fix(playbook_loader): load generated playbooks from styles/custom/

[hubooy]

Summary

Generated playbooks are invisible at render time.

lib/playbook_generator.save_playbook() writes them to styles/custom/ (:219-220), and the skills instruct agents to save them there — skills/meta/capability-extension.md:62, plus the animation and explainer proposal directors. But styles/playbook_loader.py globs only the styles/ root, and it is the loader tools/video/video_compose.py imports (:1234, :1728). So a playbook created through the documented path can never be loaded by the tool that needs it.

The two modules also disagree with each other: playbook_generator has its own load_playbook/list_playbooks that do search custom/, but nothing in the Python codebase imports that module — only the three skill docs point at it.

The practical result is that every custom playbook has to be hand-copied up one directory, leaving duplicated pairs in styles/ and styles/custom/.

Related issue

None — filing the fix directly.

Changes

• load_playbook() falls back to <styles_dir>/custom/ when the name is not found in the root.
• list_playbooks() merges both directories and dedupes.
• Semantics match what lib/playbook_generator.py:32-49 already implements: a preset wins when both exist.
• The styles_dir override parameter still works — the custom subdirectory is resolved relative to it, not hardcoded.
• FileNotFoundError now names both directories searched, instead of only the last path tried.

Testing

• python -m pytest tests/contracts/ -q — 630 passed, 7 skipped (includes the 14 playbook cases in test_phase3_contracts.py and test_taste_governance_contracts.py).
• python tests/qa/test_07_playbook_intelligence.py — 56 passed, 0 failed.
• Behavior verified against an isolated styles dir passed via the styles_dir override: a playbook present only in custom/ now loads; with the same name in both places the root preset wins; list_playbooks() dedupes the overlap; and a missing name reports both directories searched.

Checklist

• The change is focused on a single logical concern.
• I ran the relevant tests locally (make test-contracts / make test) where applicable.
• I updated docs/README if behavior or usage changed. — no doc change needed; this makes the existing docs (capability-extension.md:62 and the proposal directors) true.
• No unrelated files (build artifacts, local config) are included in the diff.

🤖 Generated with Claude Code

https://claude.ai/code/session_01GYThSL15CujvBwD1wuUmr9