Fixes

• Fixes FileDialog/OpenDialog: one unreadable entry makes the entire directory render empty (FileDialogState.GetChildren swallows the exception) #5544

Proposed Changes/Todos

• Add fix and regression unit tests.

Summary:

• Both tests fail as expected. The failure collection contains only the .. parent row, proving the current fix preserves parent navigation but still loses the readable entries when the listing call itself throws.
• Changed FileDialogState to stop using the eager Get* methods altogether for normal listing. It will enumerate with EnumerationOptions.IgnoreInaccessible = true, then still wrap each returned entry defensively as before.

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