[P2] Add internationalization support model

[spazyCZ]

Objective

Define whether and how UAAPS supports internationalization for artifact content and metadata.

Priority

P2 — Nice to Have

Details

The spec is currently English-only and has no model for localized descriptions, prompts, or locale-aware content selection.

Acceptance Criteria

• Decide whether i18n is in scope
• If yes, define a basic model for localized artifact metadata/content
• Identify affected sections and schemas

Notes

Source: work/spec-gap-analysis.md