Add Documentation for Filtering Search Results and Partial Indices in Vector Search

[asr2003]

/claim #143
Closes #143

[asr2003]

@ChuckHend I have added documentation for the where parameter in vectorize.search() and provided a example for filtering search results. Additionally, I have also included instructions on using partial indices to optimize queries especially when frequent filtering is required.

I have followed the existing documentation style and ensured that the examples are clearly structured.

Let me know if any adjustments or changes are needed. I am happy to make any necessary updates.

[asr2003]

@ChuckHend Can this be merged now? or any changes needed here?

[ChuckHend]

I like how the example uses the index with product_category and price. Can you add those values to the example.sql file so that these new docs function correctly with it?

If we add those columns to the example data, and update these changes to use where_sql as the parameter name I think this is good to merge.

[asr2003]

@ChuckHend Done with review comments

[asr2003]

@ChuckHend Are there anything from my end to fix the workflows. I think it's not related to changes of this PR

[ChuckHend]

Thank you! I think there is an issue with CI that is unrelated to this PR, so I will merge this now.