Allow store middleware to take an initial state

[maier49]

Type: feature

The following has been addressed in the PR:

• There is a related issue
• All code has been formatted with prettier as per the readme code style guidelines
• Unit or Functional tests are included in the PR

Description:
This came up in the discussion around #744 although it doesn't directly resolve the issue there.

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[codecov]

Codecov Report

Merging #782 into master will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master     #782   +/-   ##
=======================================
  Coverage   97.52%   97.52%           
=======================================
  Files         126      126           
  Lines        7927     7927           
  Branches     1824     1825    +1     
=======================================
  Hits         7731     7731           
  Misses        196      196           

Impacted Files	Coverage Δ
src/core/middleware/store.ts	100.00% <100.00%> (ø)

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