Pl/constant specs as ps

[paulflang]

Trying Catalyst#constant-specs-as-ps.
cc @isaacsas

[paulflang]

@isaacsas : SciML/Catalyst.jl#522 works for me locally. I just don't know how to best get it to work here on CI, cause when I push the Manifest I get an error that it was created with a different Julia version (using 1.7 locally) and if I don't push it I would assume that it does not find your Catalyst branch. Do I need to fix this? If so how?
Otherwise Catalyst#constant-specs-as-ps seems good to merge from my perspective.

[isaacsas]

Sounds good. I’ll try to fix up the API stuff and then make a new breaking release. Should be tomorrow evening at the latest if that works.

[paulflang]

Great, thanks!

[codecov]

Codecov Report

Merging #72 (a9eae61) into main (0b4dcb8) will increase coverage by 0.04%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main      #72      +/-   ##
==========================================
+ Coverage   98.61%   98.66%   +0.04%     
==========================================
  Files           1        1              
  Lines         217      224       +7     
==========================================
+ Hits          214      221       +7     
  Misses          3        3              

Impacted Files	Coverage Δ
src/reactionsystem.jl	98.66% <100.00%> (+0.04%)	⬆️

📣 Codecov can now indicate which changes are the most critical in Pull Requests. Learn more

[paulflang]

@anandijain , this PR treats constant species as parameters. It assigns them the new isconstantspecies=true metadata in Catalyst v12 (IIUC this allows them to participate as reactants/products and enable correct interpretation of mass action kinetics). Could you please review?

[anandijain]

lgtm