catalog-hygienelisted

# Catalog Hygiene ## Purpose Provide a standardized, static methodology for keeping translation catalogs correct and complete, and for making a UI ready for right-to-left languages. A catalog rots the moment code and translations drift: keys used in code but missing from a locale render raw ids to users, keys left in the catalog after a feature is deleted are paid-for cruft, and values that were copy-pasted from English *look* translated but ship the wrong language. RTL readiness is the other half, a layout full of physical `left`/`right` CSS silently breaks in Arabic and Hebrew. ## Catalog Health Checks Cross-reference the code's translation calls against every locale file and report: | Check | Definition | Impact | |---|---|---| | Missing key | used in code, absent in a locale | fallback text or a raw key shown to users | | Unused key | in the catalog, referenced nowhere | dead weight; wasted translation spend | | Untranslated value | target value byte-equal to the source | looks done, ships the source language | | Placeholder drift | `{name}`/`{count}` set differs across locales | `undefined` in the string or a formatter throw | | ICU error | malformed `plural`/`select`, unbalanced braces | renders literally or throws at runtime | | Missing plural category | locale lacks a CLDR form its grammar needs | wrong number agreement for real inputs | Measure **coverage per locale** = translated keys ÷ source keys, and treat the source locale (usually `en`) as the reference set