chore(tao): migrate decorated-window-tao to Compose 1.12.0-rc01 - #354

Why

Get ahead of the Compose 1.12 release: the no-AWT decorated-window-tao
backend drives Compose's internal androidx.compose.ui.scene.* APIs directly,
so it's the one module that breaks on a minor Compose bump.

Rebased on current main (the previous head conflicted after the Tao
JetBrains-style refactor). Bumped from 1.12.0-beta02 to 1.12.0-rc01
(latest published RC — 1.12.0 stable is still not out). Catalog flip to
stable later is one line.

What changed in the 1.12 ComposeScene API

• ComposeScene.render(canvas, nanoTime) removed → three steps:
  FrameRecomposer.performFrame(nanoTime) + ComposeScene.measureAndLayout() +
  ComposeScene.draw(canvas).
• Scene factories (Canvas/PlatformLayersComposeScene) drop coroutineContext
  • invalidate; now take a FrameRecomposer (which owns the frame clock) +
    invalidateLayout / invalidateDraw. The manual per-host BroadcastFrameClock
    and frameClock.sendFrame() calls are gone.
• ComposeSceneContext.createLayer: compositionContext → consumePointerInputOutside.
• ComposeSceneLayer.setContent(parentCompositionContext, content) + new abstract
  consumePointerInputOutside property.
• LocalSystemTheme is now internal and typed as Skiko SystemTheme.
  ProvideNucleusSystemTheme still feeds Nucleus's live dark-mode detector into
  that local (INVISIBLE_REFERENCE, same pattern as other Compose-internal
  bridges).

Approach

Scene create/render/dispose plumbing is centralized in TaoSceneBundle
(scene/TaoSceneBundle.kt). Each host/popup/overlay stores a TaoSceneBundle?
and keeps val scene get() = sceneBundle?.scene, so the ~20 scene?.… call
sites per file are untouched — only create/render/close move. Future Compose
bumps touch one file for the shared logic.

Behaviour is kept at parity with the 1.11 path: the paced frameNs is still fed
to the frame clock for standalone popups, and every invalidation
(invalidateLayout/invalidateDraw + the recomposer's own) funnels into the
same coalescing frame scheduler that invalidate used before.

The offscreen scene test harness (TaoSceneTestHarness) moves onto the same
bundle: recordSceneToPicture → FrameRecomposer.performFrame, which flushes
its own dispatchers around the tick.

Note: SingleComposeSceneRenderingScope

Compose Desktop's AWT path wraps the three render calls in
SingleComposeSceneRenderingScope.render, but that method is Kotlin-internal
(JVM-public, module-private) and invisible to external backends. TaoSceneBundle
inlines performFrame → measureAndLayout → draw directly. The only thing
lost vs. upstream is its isRendering-guarded invalidation de-dup — which the
old Tao code didn't have either, and the FrameDispatcher coalescing covers it.

Catalog

Fallout: AGP 9 / Java 17

Compose 1.12 also pulls AndroidX Compose 1.12 into examples:cmp-demo's Android
target, which requires AGP ≥ 9.1 and compileSdk 37. That cascades:

• agp 8.13.2 → 9.1.1 (9.2+ needs Gradle ≥ 9.4.1, we're on 9.4.0), cmp-demo
  compileSdk/targetSdk 35 → 37.
• android.builtInKotlin=false + android.newDsl=false: since AGP 9,
  com.android.application is rejected alongside the KMP plugin, which points at
  com.android.kotlin.multiplatform.library — a library plugin, unusable for
  cmp-demo (a KMP module that builds a real Android app) without splitting it into
  a separate :androidApp module. These are AGP's documented escape hatches.
• plugin-build/plugin jvmTarget 11 → 17 — AGP 9 artifacts are built for 17
  and can't be resolved by an 11-targeted consumer. User-visible: the Nucleus
  Gradle plugin now needs a Gradle daemon on JVM 17+ (mandatory since Gradle 9
  anyway; Gradle 8 + JVM 11 setups are no longer supported).
• Dropped a stray org.jetbrains.skia.Surface import from cmp-demo's
  commonMain — unused, and unresolvable on Android.

Verification

• :decorated-window-tao:compileKotlin + compileTestKotlin — clean on this
  rebase (macOS / JDK 21).
• :nucleus-application:compileKotlin, :examples:compose-demo:compileKotlin,
  :examples:extra-launcher-demo:compileKotlin.
• Headful macOS smoke with the Material 3 Expressive sample (issue Compose animation causes higher memory usage #541
  LoadingIndicator 300.dp + wavy indicators): Tao window comes up on 1.12 RC
  and paints. Whole-process phys_footprint (Activity Monitor Memory) idle →
  animating is 170 → 284 MB on Tao vs 247 → 353 MB on vanilla Compose
  Desktop. The jump is Metal GPU cache (Owned physical footprint (unmapped) (graphics)), not a 1.12/Tao regression.

Not re-run on this rebase: the full :decorated-window-tao:check suite from
the original PR (78 tests), plugin-build :plugin:check, assembleDebug for
cmp-demo, or native smoke on Windows / Linux.

Before merge

• Switch catalog compose line to 1.12.0 stable when it ships
• Re-run :decorated-window-tao:check and plugin-build checks after CI
• Run the native standalone-popup smoke tests on the three OSes
• Confirm the plugin's JVM 17 floor is acceptable as a released change