clean up clear data code

[brindy]

Task/Issue URL: https://app.asana.com/0/414235014887631/1206545081824897/f
Tech Design URL:
CC: @loremattei

Description:

• Cleans up the clear data code and makes it use the async/await API.
• Removes some unnecessary and unused abstractions.
• Removes some obsolete diagnostics.
• Moves UI refresh to the end of the animation to improve consistency (should have been like this initially tbh).
• Fixes a bug where domains which remove all the cookies might get those cookies back later.
• setcookie.net is a convenient site for testing, but feel free to use any site that will drop a cookie (e.g. after login).
• It's important to test this on iOS 17 and an earlier version of iOS as there are two paths depending on OS version.
• Added a couple of maestro tests

Steps to test this PR:

Maestro

1. Run the tests under .maestro/data_clearing_tests

Migration

1. Check out an old version of the code (main will do)
2. Set some cookies on setcookie.net and fire proof the site
3. Check the cookies are retained as expected
4. Checkout this branch and run the code
5. Check the cookies are still retained

General Usage

1. Go to setcookie.net and set a cookie (save it as a favourite too for convenience). Refresh the page to confirm it has been set.
2. Use the fire button
3. Go back to setcookie.net - cookie should gone
4. Set another cookie and fire proof the site
5. Use the fire button
6. Cookie should be retained
7. Use the fire button a couple of times in a row
8. Cookie should still be present
9. Go to settings and remove the site from the list of fireproofed sites
10. Refresh the site and the cookie should have been removed
11. Do a search and on the SERP change a setting (e.g. safe search to off)
12. Use the fire button
13. Go back to the SERP - the setting should be retained
14. Login to some websites and fireproof - check that you stay logged in.
15. Remove fireproofing - check that you are logged out

[github-actions]

	Warnings
⚠️	PR has more than 500 lines of code changing. Consider splitting into smaller PRs if possible.

Generated by 🚫 dangerJS against dd5b376

[bwaresiak]

I've tested this a lot Today, and found two issues:

1. When using Auto Clear data, fireproofing doesn't seem to work when I kill and restart the app.
2. When data clear animation is set to "None" URL is not cleared from URL bar.

Other than this good job @brindy:

• Tested both iOS 15 and 17.
• Upgrading app works fine.
• With regular animation I could not reproduce the problem with URL bar glitch/data.
• Tested various scenarios, opening, navigating, clearing, reopening, restarting... all of these worked as expected.

[bwaresiak]

Tested it this morning found two problems:

1. Auto clear doesn't seem to remove cookies on restart. :)
2. Blank Snapshot view has empty space instead of search bar.
   

[bwaresiak]

Remove? :)

[bwaresiak]

readiness or a warmup? ;)

[brindy]

@bwaresiak haven't addressed the missing bar on the empty view because I think that is not related to this change, right?

[bwaresiak]

Great job!