Add Moon Phases

It would be pretty cool if we could add at least the four major moon phases: New, First Quarter, Full, and Third Quarter. I'm not sure if it's available in any API, but it couldn't hurt to look.

Icons would be simple if they don't already exist.

Feel free to label this out of scope, I just feel like it would be a nice minimal addition to the interface for those of us interested in the phases of the moon.

Examples:
- [timeanddate.com](https://www.timeanddate.com/moon/phases/usa/dallas)

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