Jetpack Focus: New users phase menu card and overlay display logic

[hassaanelgarem]

Closes #19453

Description

This PR adds the menu card for new users. It also tweaks when the remote feature flags are updated. Instead of updating them after login is complete, we update it them during login, so they are always ready post-login.

Screenshots

Light Mode	Dark Mode

Pre-testing Instructions

• To disable the learn more button:
  • Go to JetpackFullscreenOverlayGeneralViewModel.swift line 183
  • Replace this line with return nil
  • This won't be needed in production since the learn more button will be disabled remotely by then
• To enable the new users phase on login (Not needed if using the test account)
  • Go to FeatureFlag.swift line 130
  • Replace this line with return true
  • Go to FeatureFlag.swift line 150
  • Replace this line with return "dummy_key"

Testing Instructions

1. Fresh install the app
2. Log in
3. Choose any blog
4. You should eventually land on My Site
5. Make sure the overlay is displayed
6. Dismiss the overlay
7. Make sure the card is displayed and matches the design

Regression Notes

1. Potential unintended areas of impact
   Sign-in and sign-up flows

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

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.

[hassaanelgarem]

@enejb is working on adding a test account with the new users flag enabled. It would be great to test this PR using that test account when created, to make sure the feature flags are refreshed correctly during login.

[wpmobilebot]

You can test the changes in Jetpack from this Pull Request by:

• Clicking here or scanning the QR code below to access App Center
• Then installing the build number pr19894-f814486 on your iPhone

If you need access to App Center, please ask a maintainer to add you.

[wpmobilebot]

You can test the changes in WordPress from this Pull Request by:

• Clicking here or scanning the QR code below to access App Center
• Then installing the build number pr19894-f814486 on your iPhone

If you need access to App Center, please ask a maintainer to add you.

[momo-ozawa]

@hassaanelgarem

Are we meant to be showing the "Learn more at jetpack.com" button in the overlay? I thought we were hiding this link for the new user overlay?

[hassaanelgarem]

@momo-ozawa I'm not entirely sure. I started this slack thread (p1673545326946679-slack-C04564QS0V7) to gain some clarity on this.

[hassaanelgarem]

@momo-ozawa I've applied the outcome of the slack thread in #19907 because it touches both new users and self-hosted phases.