feat(demo): add types to load functions

[quentinderoubaix]

No description provided.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 93.47%. Comparing base (da75f64) to head (2ecb5da).
Report is 1 commits behind head on main.

Additional details and impacted files

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  Coverage   93.47%   93.47%           
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  Files          67       67           
  Lines        2099     2099           
  Branches      379      379           
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  Hits         1962     1962           
  Misses         73       73           
  Partials       64       64           

Flag	Coverage Δ
e2e	83.25% <ø> (ø)
unit	84.64% <ø> (ø)

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[quentinderoubaix]

as detailed here, Svelte zero config type safety already checks the types, so this PR is not necessary