fix AI-369
#### PR Dependency Tree
* **PR #13224** 👈
This tree was auto-generated by
[Charcoal](https://github.com/danerwilliams/charcoal)
<!-- This is an auto-generated comment: release notes by coderabbit.ai
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## Summary by CodeRabbit
* **New Features**
* Introduced a loading skeleton component for artifact previews,
providing a smoother visual experience during loading states.
* Artifact loading skeleton is now globally available as a custom
element.
* **Refactor**
* Streamlined icon and loading state handling in AI tools, centralizing
logic and removing redundant loading indicators.
* Simplified card metadata by removing loading and icon properties from
card meta methods.
* **Chores**
* Improved resource management for code block highlighting, ensuring
efficient disposal and avoiding unnecessary operations.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
fix AI-313, BS-3611
#### PR Dependency Tree
* **PR #13096** 👈
This tree was auto-generated by
[Charcoal](https://github.com/danerwilliams/charcoal)
<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit
* **Refactor**
* Improved performance and resource management in code block
highlighting by using a shared highlighter instance across all code
blocks.
* Enhanced the text rendering component with additional reactive
capabilities.
* **Style**
* Updated the comment sidebar header with a new background color for
improved visual consistency.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->