Fix Wasm commonTest compilation warnings

[Copilot]

The Wasm job was failing during commonTest compilation due to missing ExperimentalWasmJsInterop opt-ins in Compose UI tests, with additional noise from invalid IntelliJ-generated _root_ide_package_ references.

• Wasm test compilation

  • Opted datacapture commonTest into kotlin.js.ExperimentalWasmJsInterop at the source-set level.
  • This covers existing Compose UI test usage without annotating individual test files/functions.

• Test source cleanup

  • Removed synthetic _root_ide_package_ qualifiers from QuantityViewFactoryTest.
  • Switched those call sites to the locally defined quantity(...) helper already in the file.

• Resulting shape

  • Keeps production code untouched.
  • Limits the fix to shared test compilation settings and one affected test file.

commonTest {
  languageSettings.optIn("kotlin.js.ExperimentalWasmJsInterop")

  dependencies {
    implementation(libs.kotlin.test)
    implementation(libs.kotest.assertions.core)
    implementation(compose.uiTest)
  }
}