build(commons): enable iosArm64 + iosSimulatorArm64 targets

Phase 2 task 10 of the iOS plan — flip on iOS targets for :commons.
Gradle dep resolution is fully green for iOS; actual Kotlin/Native
compilation runs on the macOS CI job (the dev container in which this
was authored can't extract the K/N LLVM toolchain).

Dep reshuffle to match what's actually KMP-available:

- commonMain: kept project(":quartz"), Compose Multiplatform, coil-compose,
  androidx-collection, kotlinx-collections-immutable, kotlinx-serialization-json,
  compose components-resources, androidx-lifecycle-viewmodel,
  androidx-lifecycle-runtime-compose. These all publish iosArm64 +
  iosSimulatorArm64 variants per `.module` inspection.

- jvmAndroid (NEW location): project(":nestsClient") (JVM+Android-only),
  coil-okhttp (JVM-only), markdown-commonmark / markdown-ui /
  markdown-ui-material3 (the RenderMarkdown.kt consumer is already in
  jvmAndroid), and androidx-lifecycle-viewmodel-compose (AndroidX publishes
  android + jvmStubs + linuxx64Stubs variants — no iOS, so the viewModel()
  Composable helper stays JVM-bound until we either swap to the
  org.jetbrains.androidx.lifecycle variant or accept a platform-specific
  ViewModel access pattern on iOS).

- libs.versions.toml: adds androidx-lifecycle-viewmodel catalog entry.

- New intermediate source set iosMain → both iosArm64Main and
  iosSimulatorArm64Main depend on it (clean place for iOS-only actuals
  when KmpLock, WeakReference, etc. get their iOS implementations).

- .github/workflows/build.yml: test-quartz-ios job now also runs
  :commons:compileKotlinIosArm64 + :commons:compileKotlinIosSimulatorArm64.

.github/workflows/build.yml

@@ -226,6 +226,18 @@ jobs:
             :quartz:iosSimulatorArm64Test \
             :quartz:compileTestKotlinIosArm64
 
+      # :commons gained iosArm64 + iosSimulatorArm64 targets in Phase 2 of the
+      # iOS plan. Compile-only for now — actual UI / lifecycle wiring will
+      # land with the iosApp module in Phase 3. The container that runs Claude
+      # Code can't extract the Kotlin/Native LLVM toolchain (sandbox limit),
+      # so this is the first place commonMain Compose code is actually
+      # type-checked against an Apple Native frontend.
+      - name: Compile Commons for iOS
+        run: |
+          ./gradlew \
+            :commons:compileKotlinIosSimulatorArm64 \
+            :commons:compileKotlinIosArm64
+
       - name: Upload iOS Test Reports
         uses: actions/upload-artifact@v7
         if: failure()