## Code Review

This pull request replaces the hardcoded fallback video durations with a single source of truth, `DEFAULT_FALLBACK`, imported from `lib.custom_provider.duration_presets` across the text generation SDK tools and adds corresponding unit tests. The reviewer suggested moving the `durations` parsing logic inside the `try-except` block in `_fetch_reference_caps_with_fallback` to prevent unhandled `ValueError` exceptions when processing invalid capability data, ensuring the fallback mechanism remains robust.

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