Support MeshGradientPainter in Modifier.paint (JetBrains#3143)

[CMP-10167](https://youtrack.jetbrains.com/issue/CMP-10167) Support
`MeshGradient`

<img width="1136" height="962" alt="Screenshot 2026-06-22 at 14 47 34"
src="https://github.com/user-attachments/assets/1666ca6a-e569-4dc5-9c9d-b1d04ef9125c"
/>

## Release Notes
### Features - Multiple Platforms
- Support `MeshGradientPainter` in `Modifier.paint`

Author: MatkovIvan

compose/mpp/demo/src/commonMain/kotlin/androidx/compose/mpp/demo/MainScreen.kt

@@ -23,6 +23,7 @@ import androidx.compose.mpp.demo.graphics.Blending
 import androidx.compose.mpp.demo.graphics.BrushAndShadows
 import androidx.compose.mpp.demo.graphics.GraphicsLayerOutsets
 import androidx.compose.mpp.demo.graphics.GraphicsLayerSettings
+import androidx.compose.mpp.demo.graphics.MeshGradientDemo
 import androidx.compose.mpp.demo.textfield.android.AndroidTextFieldSamples
 import androidx.compose.mpp.demo.textfield.android.TextBrushDemo
 
@@ -32,6 +33,7 @@ private val GraphicsComponents = Screen.Selection(
     Screen.Example("Brush & Shadows") { BrushAndShadows() },
     Screen.Example("GraphicsLayerSettings") { GraphicsLayerSettings() },
     Screen.Example("GraphicsLayer Outsets") { GraphicsLayerOutsets() },
+    Screen.Example("MeshGradient") { MeshGradientDemo() },
 )
 
 val MainScreen = Screen.Selection(