BCP 47 Language Tag Parser

The `bcp47` package provides a parser for BCP 47 language tags, a critical standard used in internationalization (i18n) for identifying human languages. The current stable version is `1.2.0`, with a rapid succession of recent releases in April 2026, indicating active development or a recent relaunch. This library's core function is to parse a BCP 47 tag and return a structured object containing all extracted components, or `null` if the tag is syntactically invalid, which acts as an implicit validation mechanism. Its key differentiator lies in its focused adherence to the BCP 47 specification, offering a lightweight and precise tool for tasks like content negotiation, managing localization resources, or configuring user interface languages. Unlike broader i18n frameworks, `bcp47` provides a dedicated, minimalist solution for this specific parsing requirement.