Building a better way to write posts in multiple languages

Introduced a multilingual composer for Pages and individuals, allowing a single post to be written in multiple languages. Implemented machine translation for pre-filling content in additional languages. Redesigned storage to use 'author translations' (separate TAO objects for each language) instead of concatenation. Developed common interfaces for validation logic and caching of multilingual post metadata. Implemented server-side language selection for viewers based on preferences, locale, and posting language, defaulting to the first message with a "See Translation" option.