#3202 [GUI] Strata path encoding breaks on Windows 11 Russian localization (Mojibake and question marks in UI/model loading)

Description

There is a critical path resolution and encoding issue on Windows 11 with Russian localization when user folders are managed by OneDrive. Strata fails to handle localized Cyrillic paths properly, breaking both folder creation and model loading.

<img width="1037" height="522" alt="Image" src="https://github.com/user-attachments/assets/212af2c8-8f4e-45c2-9ca0-c92074bbed41" />

1. Folder creation issue: Instead of using the local execution path, the application attempts to prepare data in a corrupted legacy path with Mojibake characters:
C:\Documents and Settings\RobotComp\OneDrive\   㬥   \Strata
2. UI & Model loading issue: Inside the application Settings, when Strata actually tries to load the model, the path encoding breaks even further. The Chinese characters change into question marks (???), making the model completely inaccessible and preventing it from loading.
What causes this:
• Encoding Mismatch: The Chinese character 㬥 appears because the Russian system folder name "Документы" (Documents) in ANSI/CP1251 gets incorrectly interpreted as UTF-8.
• Question Marks (???): When the application subsequently attempts to read or display this invalid path during model loading, the fallback text processing replaces the unmappable characters with literal question marks, breaking the file handler.
• Environment: This behavior is highly specific to Windows 11 systems running strict Russian locale settings combined with OneDrive synchronization.
Environment:
• OS: Windows 11 (Pure Russian localization)
• Hardware: NVIDIA GeForce RTX 5060 Ti (16 GB VRAM), 32 GB RAM
• Model used: IQ3_S (Downloaded locally at C:\Users\RobotComp\Strata\Models\IQ3_S, but failing to prepare)
Steps to reproduce:
1. Use a Windows 11 PC with Russian system locale and active OneDrive backup for the "Documents" folder.
2. Launch Strata and attempt to point it to or load the local model.
3. Observe the 㬥 characters in the generated filesystem path, which then turn into question marks (???) in the settings/logs when model loading is initiated.
Suggested fix:
Enforce strict Unicode/UTF-8 path translation across the entire Windows API boundary in the engine, and avoid using legacy Documents and Settings or localized cloud-synced folders by default.