Add direct PC Switch Control profile entry points

[enaboapps]

Summary

• add a direct Switch control profiles action to the Main Window status area and tray menu
• route Main Window, tray, and Settings through one independent singleton profile window
• restore and activate an existing minimized profile window without coupling it to Settings
• cover callback wiring, tray menu behavior, singleton reuse, owner independence, and close/reopen behavior

Validation

• dotnet restore src/SwitchifyPc.sln
• dotnet build src/SwitchifyPc.sln -c Release --no-restore
• dotnet test src/SwitchifyPc.sln -c Release --no-build (520 unit, 1 integration)
• issue-specific WPF/tray tests (9 passed)

Closes #476