Implement and document a procedure for publishing timezone database information separately from the main release

[dkhalanskyjb]

The Wasm/WASI implementation of kotlinx-datetime uses the timezone database supplied by us (https://github.com/Kotlin/kotlinx-datetime?tab=readme-ov-file#note-about-time-zones-in-wasmwasi), as the platform itself does not expose the necessary data.

Someone may need to use newer versions of the timezone database while staying on the old version of kotlinx-datetime: for example, new versions may introduce unwanted behavior or remove the deprecated APIs, and the adaptation of the client code to the new version may be postponed. To support this, we need to be able to publish just the timezone database artifacts separately from the releases of the library itself.

[dkhalanskyjb]

An extra research avenue: the mappings between Windows timezones and IANA timezone identifiers do occasionally get updated (example: https://github.com/Kotlin/kotlinx-datetime/pull/523/files), and they are also tied to the main library release at the moment. We may want to be able to somehow update them separately from the core library as well.