Fix self-referential foreign key recursion

[dkattan]

Summary

• separate direct foreign-key discovery from the shared-key fallback heuristics in PropertyViewModel
• avoid recursive ForeignKeyProperty evaluation when scanning inverse/shared-key candidates
• add regression coverage for self-referential and non-conventional navigation naming

Root cause

PropertyViewModel.ForeignKeyProperty could recurse indefinitely while trying to infer shared-key one-to-one relationships from navigation properties whose direct FK could not be resolved yet. Self-referential and cross-linked navigations made that especially easy to trigger.

While investigating against Immybot, the recursion showed up in cycles like:

• Branding.OwnerTenant -> Tenant.OwnerTenant -> Tenant.OwnerTenant
• SmtpConfig.OwnerTenant -> Tenant.SmtpConfig -> SmtpConfig.OwnerTenant
• User.ImpersonatorUser -> User.CreatedByUser -> User.ImpersonatorUser

This change keeps the shared-key heuristics, but only allows them to inspect direct FK matches instead of recursively re-entering ForeignKeyProperty.

Validation

• DOTNET_ROLL_FORWARD=Major dotnet test --project src/IntelliTect.Coalesce.Tests/IntelliTect.Coalesce.Tests.csproj --framework net10.0 --no-restore
• linked Coalesce source into Immybot and ran the Coalesce CLI against ImmybotDbContext
• generation no longer stack overflows; it now proceeds to regular model validation failures in Immybot's broad model

[ascott18]

Hi @dkattan - thanks for the contribution. I see this is still a draft PR - was that intentional, or is it ready for a look?

[dkattan]

Hi @dkattan - thanks for the contribution. I see this is still a draft PR - was that intentional, or is it ready for a look?

I just marked it as ready. I'm working on a bunch of other contributions at the moment, this was just the first. Really excited to have discovered this library. I have been trying unsuccessfully to stitch something like this together for years.