[Woo Pos] FF, entry point and empty pos activity

[kidinov]

Closes: #11494

Description

Adds:

• POS FF
• POS button that visible when FF is on in the "more" screen
• Dummy POS activity

Testing instructions

• Make sure that in release mode the POS button is not visible and visible and opens POS activity in debug mode

Images/gif

https://github.com/woocommerce/woocommerce-android/assets/4923871/66038a7f-2332-40bc-b772-f39b501459ed

• [x] I have considered if this change warrants release notes and have added them to RELEASE-NOTES.txt if necessary. Use the "[Internal]" label for non-user-facing changes.

[wpmobilebot]

📲 You can test the changes from this Pull Request in WooCommerce Android by scanning the QR code below to install the corresponding build.

	App Name	WooCommerce Android
	Flavor	Jalapeno
	Build Type	Debug
	Commit	c6199cc12a6af64b36a62d4abd0f3f2ce22e4f1a
	Direct Download	woocommerce-prototype-build-pr11502-c6199cc.apk

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 30.43478% with 16 lines in your changes are missing coverage. Please review.

Project coverage is 40.83%. Comparing base (796a359) to head (c6199cc).

Files	Patch %	Lines
...ocommerce/android/ui/woopos/root/WooPosActivity.kt	0.00%	10 Missing :warning:
...ocommerce/android/ui/moremenu/MoreMenuViewModel.kt	66.66%	3 Missing :warning:
...m/woocommerce/android/ui/woopos/IsWooPosEnabled.kt	0.00%	2 Missing :warning:
...kotlin/com/woocommerce/android/util/FeatureFlag.kt	50.00%	0 Missing and 1 partial :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## trunk #11502 +/- ## ============================================ - Coverage 40.83% 40.83% -0.01% Complexity 5180 5180 ============================================ Files 1068 1070 +2 Lines 62285 62308 +23 Branches 8496 8498 +2 ============================================ + Hits 25437 25444 +7 - Misses 34561 34576 +15 - Partials 2287 2288 +1 ```

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