feat: gate search filters to prevent display when disabled in remote config

[aminamos]

Summary:

Resolves #189.
Updates filter gating logic so that feature-flagged search filters (e.g. Seal of Reliability) are completely hidden from the filter drawer when disabled in remote config.

Expected behavior:

Disabled filter controls do not appear as disabled chips in the search UI.

Testing tips:

1. Checkout feat/189-filter-gating.
2. Run yarn test.
3. Open search filters on /feeds with default remote config.

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• Add or update any needed documentation to the repo
• Format the title like "feat: [new feature short description]". Title must follow the Conventional Commit Specification(https://www.conventionalcommits.org/en/v1.0.0/).
• Linked all relevant issues
• Include screenshot(s) showing how this pull request works and fixes the issue(s)

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[emmambd]

Hi @aminamos, this work has to be done internally on our team due to missing functionality here.

As a result, I'm closing this PR.