Make volume calculation in preprocessor function `volume_statistics` lazy

[bouweandela]

Description

Make calculating the volume lazy.

Closes #647

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[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 94.51%. Comparing base (8d3d366) to head (b0a20ae). Report is 40 commits behind head on main.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #2436 +/- ## ======================================= Coverage 94.51% 94.51% ======================================= Files 246 246 Lines 14024 14027 +3 ======================================= + Hits 13255 13258 +3 Misses 769 769 ```

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