fix: business contract review engine v2.1 hardening - dead code cleanup, payment weak-hint disambiguation, contract-party inference priority, LLM error surfacing, established_facts wiring
Restore removed explanatory content as sheets/NOTES.md
Restructure sheets to flat tables for GitHub table rendering (B2)
Translate all sheets and examples to English (English filenames)
Translate all sheets and examples to English (English filenames)
v2.4: Add posture-emotion reference table (Section D) to Composition & Shots
Upgrade to v2.3: honest adaptable framing, domestic API syntax flow, DALL-E 3 deprecation
Add Apache-2.0 LICENSE, .gitignore, .gitattributes, examples