Allow to recalculate cart prices

[mamhoff]

Summary

This adds a preference that allows implementers to choose to have the order updater recalculate cart prices.

Fixes #6206

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 89.48%. Comparing base (f8779d6) to head (b3b5e56).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #6399   +/-   ##
=======================================
  Coverage   89.48%   89.48%           
=======================================
  Files         980      980           
  Lines       20438    20446    +8     
=======================================
+ Hits        18289    18297    +8     
  Misses       2149     2149           

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[tvdeyen]

Long overdue! Thanks

[jarednorman]

Looks good.

@forkata Can you verify if this impacts the in-memory order updater.

[forkata]

Looks good.

@forkata Can you verify if this impacts the in-memory order updater.

@jarednorman Since this is all new code, we can rebase over this change and incorporate it in our work!

[forkata]

Love this configuration and functionality @mamhoff! One thing I've been thinking about is if it makes sense to introduce some kind of return value object from the recalculate method. I don't have a good solution for that and I don't think it should be part of this change, but I am thinking of the use case where we want to communicate a price change when advancing from cart to checkout for example, through a flash etc.