[camera_windows] Fall back to a physical stream for cameras that reject preferred-stream selectors

[llfbandit]

Fixes #140014

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Code Review

This pull request updates the Windows camera implementation to resolve and use explicit source stream indices for preview, record, and photo capture, falling back to physical streams when preferred-stream selectors are rejected. This change addresses initialization failures on multi-stream USB cameras. The review feedback suggests modifying the stream resolution logic to prefer the first encountered video capture stream rather than the last.