Use mapping from viewconfig when generating thumbnail

[frcroth]

URL of deployed dev instance (used for testing):

• https://___.webknossos.xyz

Steps to test:

• Check http://localhost:9000/api/datasets/sample_organization/test-agglomerate-file/layers/segmentation/thumbnail?w=200&h=200
• In the test-agglomerate-file dataset set the mapping to agglomerate_view_70
• Save the view config
• Check http://localhost:9000/api/datasets/sample_organization/test-agglomerate-file/layers/segmentation/thumbnail?w=200&h=200 again (hard refresh)

Issues:

• fixes #6305

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(Please delete unneeded items, merge only when none are left open)

• [x] Updated changelog

Summary by CodeRabbit

• New Features

  • Enhanced annotation capabilities with the ability to add metadata to Trees and Segments.
  • Summary row added to the time tracking overview for better task management.
  • Improved slider functionality for easier value adjustments and resets.
  • Enhanced search functionality to find unnamed segments by their full default name.
  • Thumbnails for datasets now utilize selected mapping from view configuration.

• Bug Fixes

  • Resolved issues with dataset uploads, bbox export menu, and sharing tokens.
  • Fixed automatic expansion of groups in skeleton searches and zarr streaming bugs.

• Improvements

  • Increased loading speeds for precomputed meshes.
  • Admins can now view and cancel all jobs with ownership displayed in the job list.