Also make markdown components stable

[mikepenz]

Description

• fix stability for markdown components

Fixes # (issue)

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no API changes)
• Build configuration change
• Other (please describe):

[Copilot]

Pull Request Overview

This PR marks markdown rendering components as immutable to improve Compose stability and tooling optimizations.

• Added and imported @Immutable for Compose runtime annotations
• Replaced @Stable on the MarkdownComponents interface with @Immutable
• Converted DefaultMarkdownComponents to a @Immutable data class

Comments suppressed due to low confidence (2)

multiplatform-markdown-renderer/src/commonMain/kotlin/com/mikepenz/markdown/compose/components/MarkdownComponents.kt:95

• [nitpick] Annotating the interface MarkdownComponents as @Immutable may be misleading since interfaces alone don't guarantee immutability of all implementations. It’s usually better to keep the interface @Stable and only mark concrete implementations with @Immutable.

@Immutable

multiplatform-markdown-renderer/src/commonMain/kotlin/com/mikepenz/markdown/compose/components/MarkdownComponents.kt:121

• [nitpick] Converting DefaultMarkdownComponents into a data class generates copy and componentN functions that may not be necessary here. If you don't need value semantics or copies, a regular class annotated with @Immutable could reduce generated bytecode.

private data class DefaultMarkdownComponents(