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1. Is this request related to a challenge you're experiencing? Tell me about your story.

I've been working with knowledge retrieval and need to filter documents based on select variables. Currently, only string, number and time variables appear in the metadata filtering dropdown, while select variables are completely absent despite being functionally equivalent to strings at runtime. This prevents me from creating filters that use dropdown selection variables, which are essential for my use case.

2. Additional context or comments

The metadata filtering UI correctly shows string-type variables but ignores select-type variables, even though they could be treated identically for filtering purposes. I believe that this requires modifying the MetadataFilteringVariableType enum to include 'select' and updating the relevant components to handle select variables properly.

3. Can you help us with this feature?

• I am interested in contributing to this feature.