Remove j and block ex coef#220

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MetBenjaminWent wants to merge 4 commits intoMetOffice:mainfrom

MetBenjaminWent:ex_coef

Commits on Jan 21, 2026

Remove j, builds, KGOs and improves performance
MetBenjaminWent
committed

Commits on Feb 3, 2026

Commits on Feb 4, 2026

Merge branch 'MetOffice:main' into ex_coef
MetBenjaminWent
authored