introducing @register_product decorator to make product instances re-usable (previously calling .register() from a subsequent builder invalidated the former builder/particulator)

[slayoo]

No description provided.

[codecov]

Codecov Report

Attention: Patch coverage is 98.84393% with 2 lines in your changes missing coverage. Please review.

Project coverage is 84.20%. Comparing base (f8849c4) to head (c6dc384).

Files	Patch %	Lines
.../size_spectral/particle_concentration_activated.py	71.42%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1370      +/-   ##
==========================================
+ Coverage   84.06%   84.20%   +0.13%     
==========================================
  Files         368      369       +1     
  Lines        9026     9106      +80     
==========================================
+ Hits         7588     7668      +80     
  Misses       1438     1438              

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.