Simplify navigating to the Notifications tab

[crazytonyli]

This PR moves a few functions from the RootViewPresenter protocol definition to its extension, so that we can have one implementation to be shared by different conformations.

There should be no changes to how the app behaves. You can test the changes by using the following universal links:

• https://wordpress.com/notifications takes the app to the root of navigation tab.
• https://wordpress.com/me/notifications takes the app to the notification settings modal.

Regression Notes

1. Potential unintended areas of impact

2. What I did to test those areas of impact (or what existing automated tests I relied on)

3. What automated tests I added (or what prevented me from doing so)

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.

Testing checklist:

• [ ] WordPress.com sites and self-hosted Jetpack sites.
• [ ] 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]

📲 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	pr23570-e89fbad
	Version	25.3
	Bundle ID	com.jetpack.alpha
	Commit	e89fbad9b6621a1baa1a349101836682a99c1a40
	App Center Build	jetpack-installable-builds #9658

Automatticians: You can use our internal self-serve MC tool to give yourself access to App Center if needed.

[wpmobilebot]

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

	App Name	WordPress Alpha
	Configuration	Release-Alpha
	Build Number	pr23570-e89fbad
	Version	25.3
	Bundle ID	org.wordpress.alpha
	Commit	e89fbad9b6621a1baa1a349101836682a99c1a40
	App Center Build	WPiOS - One-Offs #10615

Automatticians: You can use our internal self-serve MC tool to give yourself access to App Center if needed.