Add theme: Serenity

[Bluemoondragon07]

Network interactions have been removed.

I am submitting a new Community Theme

Repo URL

Link to my theme: https://github.com/Bluemoondragon07/Obsidian-Serenity

Theme checklist

• My repo contains all required files (please do not add them to this obsidian-releases repo).
  • manifest.json
  • theme.css
  • The screenshot file (16:9 aspect ratio, recommended size is 512px by 288px for fast loading).
• I have indicated which modes (dark, light, or both) are compatible with my theme.
• I have read the developer policies at https://docs.obsidian.md/Developer+policies, and have assessed my theme's adherence to these policies.
• I have read the tips in https://docs.obsidian.md/Themes/App+themes/Theme+guidelines and have self-reviewed my theme to avoid these common pitfalls.
• I have added a license in the LICENSE file.
• My project respects and is compatible with the original license of any code from other themes that I'm using. I have given proper attribution to these other themes in my README.md.

[github-actions]

Hello!

I found the following issues in your theme submission

Errors:

❌ Your manifest does not have the required minAppVersion property.

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[joethei]

I've added in the theme back in it's original place.
(The order in the list is important for the ordering in the theme modal when sorting by age.