LookupPath() fails to retrieve fields marked as required or optional

[FletcherCuttingMachShip]

What version of CUE are you using (cue version)?

cuelang.org/go v0.10.0

Does this issue reproduce with the latest stable release?

Yes

What did you do?

I have the following test:

func Test_cue(t *testing.T) {
	cuectx := cuecontext.New()
	schema := cuectx.CompileBytes([]byte(`
		person: {
			name!: string
		}
	`))

	if err := schema.Validate(); err != nil {
		t.Fatalf("failed to compile schema: %s", err)
	}

	cuePath := cue.ParsePath("person.name")

	if err := cuePath.Err(); err != nil {
		t.Fatalf("failed to parse path: %s", err)
	}

	value := schema.LookupPath(cuePath)

	if err := value.Err(); err != nil {
		t.Fatalf("failed to lookup path: %s", err)
	}
}

Worth noting: This also happens if the field has a ?.

What did you expect to see?

I expected to retrieve the person.name value without any errors.

What did you see instead?

The test failed with the following error:

failed to lookup path: person: field not found: name