[Follow Up] #1938: P3A alignment and UI fixes for onboarding

[soner-yuksel]

Summary of Changes

Fixing p3a popover tablet size width, switch toggle location, also fixes dismiss presentation after moving onboarding to different target so there will not be any view shown before dismiss

No ticket created cause the feature is not tested yet.

This pull request reference #1938

Submitter Checklist:

• Unit Tests are updated to cover new or changed functionality
• User-facing strings use NSLocalizableString()
• New or updated UI has been tested across:
  • Light & dark mode
  • Different size classes (iPhone, landscape, iPad)
  • Different dynamic type sizes

Screenshots:

Reviewer Checklist:

• Issues include necessary QA labels:
  • QA/(Yes|No)
  • bug / enhancement
• Necessary security reviews have taken place.
• Adequate unit test coverage exists to prevent regressions.
• Adequate test plan exists for QA to validate (if applicable).
• Issue and pull request is assigned to a milestone (should happen at merge time).