Improving `CliOption` implementation

[ForteScarlet]

Previously, CliOption was coupled with the Kotlin plugin module, which led to the Gradle Plugin also referencing the Kotlin plugin module, and thus the Kotlin Compiler's dependencies, when it wanted to reuse the content.

Before #65 was changed, this issue was not exposed. However, after it was changed, this issue led to #90.

So: consider a standalone CliOption that can be reused but doesn't lead to propagation of Kotlin compiler dependencies.

[ForteScarlet]

After #93 the configuration module and cli module are independent, theoretically... more flexible KSP support is also achievable. Configuration information can be shared, and behavior can be more consistent. Maybe we can consider #29, generating top-level functions?