[Peek]Fix foreground window setting

[jaimecbernardo]

Summary of the Pull Request

After #26364, the way to bring the Peek window to the foreground doesn't seem to be working correctly. It sometimes seems to bring keyboard input in but not mouse input, making the way that we try to detect loss of focus not work when the option to "Automatically close the Peek window after it loses focus" not work.

Changed the way we bring the Peek Window to the foreground mimic what we do on other PowerToys, which is to first send some mouse simulated mouse input and then bring the window to the foreground. This seems to be more stable.

PR Checklist

• Closes: [Peek] When losing focus it should close automatically #26366
• 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

Validation Steps Performed

Tested switching files multiple times with both the "Automatically close the Peek window after it loses focus" on and off, both on the Desktop and on an Explorer window.

[gokcekantarci]

I tested it and the code looks good

[davidegiacometti]

I was wondering if we can use single instance instead of this hack https://learn.microsoft.com/en-us/windows/apps/windows-app-sdk/applifecycle/applifecycle-instancing

[jaimecbernardo]

I was wondering if we can use single instance instead of this hack https://learn.microsoft.com/en-us/windows/apps/windows-app-sdk/applifecycle/applifecycle-instancing

What do you mean? Wouldn't that mean cold booting every time?

[davidegiacometti]

I was wondering if we can use single instance instead of this hack https://learn.microsoft.com/en-us/windows/apps/windows-app-sdk/applifecycle/applifecycle-instancing

What do you mean? Wouldn't that mean cold booting every time?

The idea was to make it single-instance using WinAppSDK lifecycle APIs. When a second process is launched redirect the activation to the running instance. I have done a quick test with Hosts File Editor (we are already using this to make it single-instance) but I am not able to bring up the running window when a second process is launched. Never mind, the PR solution looks fine!