Issue: Hyphenation Locale Resolution 2026-08-20

issue024 [ ] Hyphenation accepts common locale spelling but selects the wrong dictionary

Status: Runtime fix verified by task039; user-visible confirmation remains pending.
Summary: de-CH and de-DE normalize to underscore forms but are looked up in the short-code registry, where they can resolve to the first arbitrary German dictionary rather than the exact locale.
Expected vs Actual: Equivalent de_CH/de-CH spellings should select hyph_de_CH.dic; current de-CH selects hyph_de_AT.dic.
Related: ekp-hyphen.el, plan_dictionary_governance_20260728.md, task039.
Fix: Raw and normalized exact locale keys are checked before the documented short-code fallback.
Verification: Locale-equivalence ERT 11/11 and full dictionary gates pass.
Resolved At: Pending user-visible confirmation.
Resolved By: Developer implementation and verification.
Commit: Pending hardening commit.