[Admin] Add filter toolbar for enhanced search functionality

[rainerdema]

Summary

This PR introduces a temporary filter toolbar.
This addition is necessary due to the transition from the old admin product page, and to maintain continuity of certain features, specifically the 'With Deleted' option.
This filter toolbar will be further updated in the future to accommodate more sophisticated UI/UX.

Here's an example of how you can add a new filter to see only 'promotionable' products:

1. First, include 'promotionable' in the ransackable attributes in the Spree::Product model.
2. Then, add a filter in the filters composition in the product index:

def filters
  [ 
  .
  .
    {
      name: 'q[promotionable_eq]',
      value: true,
      label: "Only promotionable",
    },
  ]
end

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[codecov]

Codecov Report

Merging #5296 (fd896c7) into nebulab/admin (226ea39) will increase coverage by 0.00%.
The diff coverage is 100.00%.

❗ Current head fd896c7 differs from pull request most recent head c3e90b8. Consider uploading reports for the commit c3e90b8 to get more accurate results

@@              Coverage Diff               @@
##           nebulab/admin    #5296   +/-   ##
==============================================
  Coverage          88.56%   88.57%           
==============================================
  Files                599      599           
  Lines              14573    14579    +6     
==============================================
+ Hits               12907    12913    +6     
  Misses              1666     1666           

Files Changed	Coverage Δ
...mponents/solidus_admin/products/index/component.rb	92.50% <100.00%> (+0.39%)	⬆️
...app/components/solidus_admin/ui/table/component.rb	100.00% <100.00%> (ø)

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[elia]

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