Release v5.4.2 section depth refresh

[Emily2040]

Summary

• Releases v5.4.2 with deeper section-by-section skill routing and source-gated workflow guidance.
• Adds Runway/Volcengine API workflow notes, mode-specific examples, richer multilingual vocab, and classified community-mining patterns.
• Replaces the README hero with a stronger cinematic Seedance production-control image.
• Expands eval coverage to 41 cases, including audio-reference conflicts, edit/extend routing, FLF2V, VFX repair, shot continuity, and gallery-safety classification.

Validation

• python scripts/validate_skills.py --strict
• python scripts/content_audit.py --strict
• python scripts/eval_schema_check.py --strict
• python scripts/design_audit.py --strict
• python scripts/source_registry_check.py --strict
• python scripts/vocab_schema_check.py --strict
• git diff --check