simulate: a claim pinned to a revision that calls a changed function is left out #516

What happened?

When a run changes a function, simulate also renders Manual XRs pinned to a Composition revision whose pipeline calls that function (pinnedFunctionChangeXRs in internal/diff/diffprocessor/comp_processor.go). Their revision doesn't change, but the function it calls does.

That check doesn't cover claims. pinnedRevisionCallsChangedFunction only matches a revision whose compositeTypeRef is the object's own group and kind. A claim's kind isn't, so a pinned claim stays filtered out as Manual, and nothing is predicted for it.

Claims only exist for legacy cluster-scoped XRs, so this misses exactly those users: a claim bound to a Manual XR whose revision calls the changed function gets no entry.

The code has a TODO(jcogilvie) for this at pinnedRevisionCallsChangedFunction. Fixing it means checking the claim's backing XR instead, and routing that XR's key to the render.

Raised in review on #436: #436 (comment)

How can we reproduce it?

1. Install a legacy cluster-scoped XRD that offers a claim, and a Composition whose pipeline calls function F.
2. Create a claim with compositionUpdatePolicy: Manual, so its XR is pinned to the current revision.
3. Change F in a project, without changing the Composition.
4. Run crossplane project simulate.
5. The claim has no entry. A namespaced XR pinned to the same kind of revision does get one.

What environment did it happen in?

• Crossplane CLI version: main at 4f5fc53
• Platform (e.g., linux/amd64): any
• Crossplane version (if applicable): v2, with a legacy cluster-scoped XRD