Filter out soft deleted users from lessons, quizzes and groups

[AlexVelezLl]

Summary

• Filter out soft-deleted users from lessons, quizzes, and groups in the backend, to prevent the frontend from having problems when trying to access soft-deleted users' information.
• Adds a filter argument to the annotate_array_aggregate method, to allow passing filters to the aggregate function.
  • This way, we can filter out soft-deleted users from the learners' list of lessons, quizzes, and groups.
• Filter out soft-deleted users from the learners' lists of draft quizzes.

Grabacion.de.pantalla.2025-10-02.a.la.s.8.31.30.a.m.mov

References

Closes #13793.

Reviewer guidance

Follow the steps described on #13793.

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Build Artifacts

Asset type	Download link
PEX file	kolibri-0.19.0b0.dev0_git.61.g08502a79.pex
Windows Installer (EXE)	kolibri-0.19.0b0.dev0+git.61.g08502a79-windows-setup-unsigned.exe
Debian Package	kolibri_0.19.0b0.dev0+git.61.g08502a79-0ubuntu1_all.deb
Mac Installer (DMG)	kolibri-0.19.0b0.dev0+git.61.g08502a79.dmg
Android Package (APK)	kolibri-0.19.0b0.dev0+git.61.g08502a79-0.1.6-debug.apk
Raspberry Pi Image	kolibri-pi-image-0.19.0b0.dev0+git.61.g08502a79.zip
TAR file	kolibri-0.19.0b0.dev0+git.61.g08502a79.tar.gz
WHL file	kolibri-0.19.0b0.dev0+git.61.g08502a79-py2.py3-none-any.whl