feat(texteditor): add text alignment toggling buttons

[habibayman]

Summary

This is still a WIP 🚧 Just to make it easier for anyone who wants to check my progress.

so far what's missing is:

• the extension isn't working with custom nodes like:
  • image
  • small text
• think about how will the alignment be converted to markdown!!

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References

• Figma Design

• currently this PR represents part of Update rich text editor to flexible, extensible rich text editing framework #5049

• fixes [Rich Text Editor]: add a toggle text alignment (R/L) button #5385

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Reviewer guidance

[learning-equality-bot]

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