Posts & Pages: Move authors filter button to navigation bar

[kean]

Fixes #21715

To test:

• Verify that the authors filters is now displayed in the navigation bar
• Verify that the filter is available for both Posts and Pages
• Verify that after a fresh install the default filter is "Everyone"

Regression Notes

1. Potential unintended areas of impact: Posts & Pages
2. What I did to test those areas of impact (or what existing automated tests I relied on): manual
3. What automated tests I added (or what prevented me from doing so): n/a

PR submission checklist:

• I have completed the Regression Notes.
• I have considered adding unit tests for my changes.
• I have considered adding accessibility improvements for my changes.
• I have considered if this change warrants user-facing release notes and have added them to RELEASE-NOTES.txt if necessary.

UI Changes testing checklist:

• Portrait and landscape orientations.
• Light and dark modes.
• Fonts: Larger, smaller and bold text.
• High contrast.
• VoiceOver.
• Languages with large words or with letters/accents not frequently used in English.
• Right-to-left languages. (Even if translation isn’t complete, formatting should still respect the right-to-left layout)
• iPhone and iPad.
• Multi-tasking: Split view and Slide over. (iPad)

[wpmobilebot]

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	App Name	WordPress Alpha
	Configuration	Release-Alpha
	Build Number	pr21766-c9cfffd
	Version	23.4
	Bundle ID	org.wordpress.alpha
	Commit	c9cfffd
	App Center Build	WPiOS - One-Offs #7423

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[wpmobilebot]

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

	App Name	Jetpack Alpha
	Configuration	Release-Alpha
	Build Number	pr21766-c9cfffd
	Version	23.4
	Bundle ID	com.jetpack.alpha
	Commit	c9cfffd
	App Center Build	jetpack-installable-builds #6452

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[momo-ozawa]

Hey @kean, the new authors filter looks great! A few things:

• Should default to "Me" or "Everyone"? "Me" is the default filter on mobile iOS, but it's "Everyone" on web. cc: @zwarm @AjeshRPai
• I don't see the author filter on Pages for a site that should display filters - this should be resolved by applying this change from trunk

[zwarm]

• Should default to "Me" or "Everyone"? "Me" is the default filter on mobile, but it's "Everyone" on web.

@momo-ozawa - On Android, fresh install, "Everyone" is selected as the default. I vote for staying consistent with the web, but will go with the majority.

[kean]

Other folks also agree, and there is an existing task for that #16593. I'm going with "Everyone" by default.

[kean]

@momo-ozawa, I addressed both of these issues. Thank you!