[Quick Accent] fix showing selector window

[taras-janea]

Summary of the Pull Request

Fix the displaying selector window after the user login.

PR Checklist

• Closes: Quick Accent popup window is blank #20807
• Communication: I've discussed this with core contributors already. If work hasn't been agreed, this work might be rejected
• Tests: Added/updated and all pass
• Localization: All end user facing strings can be localized
• Dev docs: Added/updated
• New binaries: Added on the required places
  • JSON for signing for new binaries
  • WXS for installer for new binaries and localization folder
  • YML for CI pipeline for new test projects
  • YML for signed pipeline
• Documentation updated: If checked, please file a pull request on our docs repo and link it here: #xxx

Detailed Description of the Pull Request / Additional comments

Validation Steps Performed

Scenario #1

1. Log-in using userA
2. Run QuickAccent and insert some letter
3. Log-in using userB
4. Log-in using userA
5. Run QuickAccent and insert some letter

Scenario #2

1. Log-in via RDP
2. Run QuickAccent and insert some letter
3. Close RDP connection, keep session alive
4. Connect again
5. Run QuickAccent and insert some letter

In both these scenarios 0.64 version shows a blank rectangle.
The latest version from the main (with improved UI) is not showing a window at all.

[damienleroy]

I can't believe the solution was so simple... Good catch!
LGTM

[jaimecbernardo]

I've added some fixes here.
The problem with calculating the position when the window has been hidden means that it won't have the correct size. Because of this I had some accents clipped from view when it's on the bottom right, for example.

Not related to this PR and also present in main was the issue that offsets were not being applied in the same way in left vs right or top vs bottom positions. The reason for this being that margins were added to the base grid and then a offset applied. This made our offset calculation make little sense, so I've removed the margins and added a little offset to make it look similar.

[jaimecbernardo]

LGTM! Great work. I've applied some fixes on top of it and will merge soon.