Implement Hugo build validation for localized content across all projects

Current issue is a follow up on this thread: #183 (comment 2621036727)

Goal

Add Hugo build testing to i18n pipelines to catch rendering (or any other, TBD) issues in translated documentation before deployment. Each project should implement Hugo validation following their existing patterns, for example: GitLab with docs-i18n hugo_build, Runner with docs:check i18n Hugo build, etc.