Kotlin Multiplatform Product Flavors Gradle Plugin - Bring Android-style product flavors to KMP

Configures a Kotlin Multiplatform project to use Firebase via cmp-firebase. Adds the cmp-firebase dependency at a matching version, forces isStatic=true on every Apple framework (Firebase's SwiftPM products are static libraries, so a dynamic framework compiles and links but crashes at launch), and fails the build with an actionable message when Kotlin is below 2.4.20, where the transitive SwiftPM resolution that pulls firebase-ios-sdk does not exist and the build otherwise dies with an unrelated-looking "ld: framework 'FirebaseCore' not found". Documentation: https://github.com/MobileByteLabs/KmpToolkit/blob/dev/cmp-firebase-gradle-plugin/README.md