[Light Switch] Follow Night Light mode (#43683)

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fix/what does it change/how was it tested (even manually, if necessary)?
-->
## Summary of the Pull Request
Introduces a new mode that will have Light Switch follow Windows Night
Light.

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## PR Checklist

- [x] Closes: https://github.com/microsoft/PowerToys/issues/42457
- [x] **Communication:** I've discussed this with core contributors
already. If the work hasn't been agreed, this work might be rejected
- [ ] **Tests:** Added/updated and all pass
- [x] **Localization:** All end-user-facing strings can be localized
- [ ] **Documentation updated:** If checked, please file a pull request
on [our docs
repo](https://github.com/MicrosoftDocs/windows-uwp/tree/docs/hub/powertoys)
and link it here: #xxx

<!-- Provide a more detailed description of the PR, other things fixed,
or any additional comments/features here -->
## Detailed Description of the Pull Request / Additional comments
Strictly follows the state of Night Light. When NL is on, LS will be
switch to dark mode and when NL is off, LS will switch to light mode
(with respect to the users system/app selection).

<!-- Describe how you validated the behavior. Add automated tests
wherever possible, but list manual validation steps taken as well -->
## Validation Steps Performed
Turn on Follow Night Light mode
Change night light!

## Notes

.github/actions/spell-check/expect.txt

@@ -144,6 +144,8 @@ BLENDFUNCTION
 blittable
 Blockquotes
 blt
+bluelightreduction
+bluelightreductionstate
 BLURBEHIND
 BLURREGION
 bmi
@@ -1115,6 +1117,7 @@ NEWPLUSSHELLEXTENSIONWIN
 newrow
 nicksnettravels
 NIF
+nightlight
 NLog
 NLSTEXT
 NMAKE