Fix tracking validation

[joanagmaia]

Changes proposed ✍️

What

🤖 Generated by Copilot at 1eb659e

This pull request fixes a bug that prevented the advanced filter feature from working properly for various query endpoints. The bug was caused by reading the filter parameter from the wrong source. The fix applies the same change from F0L24R24 to all affected files in the backend/src/api directory.
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🤖 Generated by Copilot at 1eb659e

filter bug fixed
many endpoints now happy
autumn of errors

Why

How

🤖 Generated by Copilot at 1eb659e

• Fix a bug where the filter parameter was read from the query string instead of the request body for various query endpoints (link, link, link, link, link, link, link, link, link, link, link)

Checklist ✅

• Label appropriately with Feature, Improvement, or Bug.
• Add screenshots to the PR description for relevant FE changes
• New backend functionality has been unit-tested.
• API documentation has been updated (if necessary) (see docs on API documentation).
• Quality standards are met.