Provide annotation-only artifact for JetPack Compose

[technoir42]

Current behaviour The annotations currently reside in the plugin artifact which has Kotlin compiler, KotlinPoet and Kotlin serialization among its dependencies, but annotations are supposed to be used in an Android module, where such dependencies are undesirable.

// Usage in Android library:
dependencies {
    implementation("com.figma.code.connect:plugin:1.0.0")
}

Desired behaviour 2 artifacts are provided: annotation-only artifact with minimum dependencies, and the plugin artifact.

// Usage in Android library:
dependencies {
    implementation("com.figma.code.connect:annotations:1.0.0")
}