Expand docs for multi-language support within a single workspace

Description: As a workspace admin and content editor, I want comprehensive, centralized documentation for configuring and managing multi-language support within a single workspace so that I can plan, implement, and maintain localized experiences confidently. Problem: Current documentation does not provide sufficient guidance for enabling and operating multi-language capabilities within a single workspace. This lack of detail makes it difficult to understand core concepts, setup steps, best practices, and limitations, which slows evaluation and preparation. Benefit: Enhanced documentation will reduce implementation risk and ramp-up time, clarify expectations and constraints, and empower teams to plan workflows, model content, and use APIs effectively for multi-language scenarios in one workspace.