Shared Models for KMP

Design and implement data models that work across all platforms in shared/commonMain.

Core Dependencies

// build.gradle.kts (shared module)
sourceSets {
    val commonMain by getting {
        dependencies {
            implementation("org.jetbrains.kotlinx:kotlinx-serialization-json:1.6.0")
            implementation("org.jetbrains.kotlinx:kotlinx-datetime:1.6.0")
        }
    }
}