feat: Add unread badges in sidebar filters items

[dougfabris]

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SIDE2-54
SIDE2-88

[dionisio-bot]

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[github-actions]

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Codecov Report

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Additional details and impacted files

@@                   Coverage Diff                   @@
##             feat/sidebar-filters   #36199   +/-   ##
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Flag	Coverage Δ
e2e	55.17% <0.00%> (?)
e2e-api	35.60% <ø> (?)
unit	69.93% <ø> (?)

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