Allow applications partitioning meshes to specify partition constraints (imposed by multigrid)

[mo-rickywong]

PR Summary

Sci/Tech Reviewer: @ukmo-juan-castillo
Code Reviewer: @mike-hobson

ticket:4630 relocated checks/code-path for constraints on partitions when using MultiGrid within the the partitioners. This is a check that the partitioner (or infrastructure) should not be performing (it's a Gungho Science feature).

The contraints on multigrid are being triggered if the mesh file from which a mesh was read, contained intergrid maps, regardless of whether the application had any interest in multigrid (e.g. Lfric2Lfric re-gridding). This change provides logic for applications to specify whether they are concerned with "Multigrid" constraints.

Ideally, the checks should be relocated to Gungho Science. This change achieves the desired outcome without compounding ticket:4630 complexity.

Linked PRs

• Update App calls to partition type api lfric_apps#324

Blocking PRs

• is blocked-by Lfric2lfric multi cpu lfric_apps#201

Code Quality Checklist

• I have performed a self-review of my own code
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Testing

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Sci/Tech Review

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Code Review

• All dependencies have been resolved
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[ukmo-juan-castillo]

I run the lfric_core rose stem tests successfully, everything seems in order:

Test Suite Results - lfric_core - EnforcePartitionRestrictions/run1

Suite Information

Item	Value
Suite Name	EnforcePartitionRestrictions/run1
Suite User	juan.m.castillo
Workflow Start	2026-03-05T14:18:13
Groups Run	all

Dependency	Reference	Main Like
lfric_core	mo-rickywong/lfric_core@EnforcePartitionRestrictions	False
SimSys_Scripts	MetOffice/SimSys_Scripts@2025.12.1	True

Task Information

✅ succeeded tasks - 384

[ukmo-juan-castillo]

Everything seems in order, just a minor comment

[ukmo-juan-castillo]

The print line should probably be: 'Checking partition constraints'