Create Android distribution

@michaelneale has been trailblazing to validate `tbdex-kt` (and by extension, `web5-kt`), for Android apps in https://github.com/TBD54566975/tbdex-android-example.

This uncovers a few things we can do to make these libraries more consumable by Android devs:

* Uplevel the [`AndroidKeyManager`](https://github.com/TBD54566975/tbdex-android-example/blob/main/app/src/main/kotlin/AndroidKeyManager.kt) into `web5-kt` (see dep #250 below)
* Remove exclusions an Android app developer would need to make so that this runs in the Android runtime environment (ie. [here](https://github.com/TBD54566975/tbdex-android-example/blob/main/app/build.gradle.kts#L54) and [here](https://github.com/TBD54566975/tbdex-android-example/blob/main/app/build.gradle.kts#L61))
* Create a single-dependency distro specifically for Android to get all the dependencies correctly

Dependencies of this issue:
* #250
* #217 (We will implement in the new build after tbDEX 1.0 is feature-complete as to not interrupt that work)

To preflight this approach with @jiyoontbd to her +1 before cracking work.