Latin language pack (lat) — u/v & i/j normalization + macron stripping

[bsesic]

Summary

Add a Latin language pack (lat) to TRACE, mirroring the structure of the Arabic (ara, #16) and Greek (grc, #22) packs. Unlocks Vulgate, patristic, and scholastic material.

Motivation

Latin is a planned roadmap pack (Vulgata, patristic, scholastic) and part of the cross-tradition / Hexapla-style work (roadmap Stage 6). Reuses the language-pack architecture proven by the Arabic pack.

Scope

Mirror src/tracealign/lang/arabic/:

• Normalization (normalize.py): lowercase; strip macrons / vowel-length diacritics (NFD + combining-mark removal) into text; orthographic skeleton folding — u/v unification, i/j unification, ae/æ → ae and oe/œ → oe. Keep the diplomatic form in Token.raw.
• Tokenization (tokenize.py): Latin's analog to Arabic proclitics is the set of enclitics (-que, -ve, -ne). Start conservative — likely defer enclitic splitting for v0.1.0 (document it), or split only the unambiguous -que if justified.
• Scoring tiers (scoring.py): EXACT → DIACRITICS_STRIPPED (macrons) → ORTHOGRAPHIC_VARIANT (u/v, i/j, ae/oe folding) → fuzzy, reusing the shared Reason enum values.

Acceptance criteria

• list_languages() includes lat; tokenize/align with lang="lat" work end-to-end.
• Orthographic normalization folds u/v and i/j and ae/oe into the skeleton; macrons stripped into text; diplomatic form preserved in raw.
• Tiered scoring returns reason tags from the existing Reason enum (extend only if a genuinely Latin-specific reason is justified).
• Tests follow TDD; full suite green on 3.10/3.11/3.12; flake8 clean.
• pack.version set (lat-0.1.0) and surfaced in result params.

Notes

• Rule-based and dependency-light (stdlib + existing rapidfuzz). No new third-party dependencies.
• Roadmap: planned non-Hebrew language packs (Aramaic/Greek/Latin/Arabic/Persian).