Make tree and nodes immutable, fix benchmark

[overpas]

PR-Codex overview

This PR focuses on enhancing the treemap-chart and adding a new benchmark module. It includes updates to configurations, improvements in data structures, and introduces benchmark tests for performance evaluation.

Detailed summary

• Added benchmark module with configurations and test implementations.
• Updated build.gradle.kts files for treemap-chart and benchmark.
• Refactored TreemapElement to a data class with default values.
• Improved Tree and Node classes for better immutability.
• Enhanced FocusablePopup to use Popup with properties.
• Added performance measurement to SquarifiedMeasurerTest.
• Updated AndroidManifest.xml files with new attributes.
• Introduced stability configuration in composeCompiler.

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