[pengzhendong]

Summary

• Add native Hindi–English code-mixed ITN (hi_en), reusing the existing standalone Hindi and English ITN rules. No TN pipeline is introduced.
• Keep source text in raw fields; local English extensions support Indian numbering, date punctuation and plural temperature units without modifying the standalone English grammar.
• Register the ITN-only CLI entry, package data, configuration-aware cache tests and README. --cased defaults to false, and TN rejects hi_en.

Test plan

• All 486 original fixture lines (14 files) retained verbatim, including 70 cased date lines
• Hand-written mixed-language, raw-field, escaping and n-best/mapping cases
• CLI and cache registration regressions with NeMo imports blocked
• Full project suite on the merged master baseline (20644 passed, NeMo imports blocked)
• flake8 tn itn and git diff --check