reasoning iq and attention span endpoint

See merge request !45

Attention new ui

See merge request !44

arithmetic activity fix

See merge request !43

# Conflicts:
#   web-app/backend/server.py

Minor bug fixes

See merge request !42

# Conflicts:
#   web-app/frontend/src/components/activities/ActivityContainer.jsx

attention span new ui redesign

See merge request !41

Add Activity videos and minor fixes

See merge request !40

Randika final changes

See merge request !39

# Conflicts:
#   web-app/backend/server.py

attention model optimization

See merge request !37