Fix FancyZones editor overlay on mixed-DPI multi-monitor setups

[Memphizzz]

Summary of the Pull Request

Use DPI-unaware context when positioning overlay windows to match the coordinate space from the C++ backend.

The FancyZones editor overlay windows were incorrectly positioned on secondary monitors when using different DPI scaling (e.g., 125%/150%/125%). Zones appeared shifted or clipped because they extended past monitor edges.

PR Checklist

• Closes: FancyZones - Not Capturing full screen #43363
• Closes: FancyZones not using full screen #43386
• Communication: I've discussed this with core contributors already.
• 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

Detailed Description of the Pull Request / Additional comments

Root Cause

The C++ backend uses a DPI-unaware thread to get virtual screen coordinates, but the WPF editor (PerMonitorV2 DPI-aware) interpreted these coordinates with DPI scaling applied, causing misalignment on non-primary monitors.

Fix

• EditorParameters.cpp: Use consistent virtual coordinates for all monitor properties (removed DPIAware::Convert that was only applied to dimensions)
• Monitor.cs: Reposition overlay windows using DPI-unaware context after HWND creation, matching the coordinate space from C++ backend
• NativeMethods.cs: Added SetWindowPositionDpiUnaware() using SetThreadDpiAwarenessContext to temporarily switch DPI awareness

Validation Steps Performed

Manually tested on 3-monitor setup with 125%/150%/125% DPI scaling - overlays now correctly cover each monitor's work area.

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🤖 This fix was developed with Claude Code after 6 hours of debugging DPI coordinate systems together.

[Memphizzz]

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