[project/schemas]: go types contains conflicting code if two xrd's in same api-group has integer enum field #444

What happened?

The generated go schemas from `crossplane project build`` seems to be conflicting when two XRDs in the same API group and version contain integer enums.

Example:

XRD's for custom Subnet and VirtualNetwork resources define a .spec.size integer enum with the values 8, 16, 32, 64, 128, 256, 512.

The generated models will declare the same package-level constant name for both enum types:

// Subnet model
const (
    Empty SubnetSpecSize = 8
)

// VirtualNetwork model
const (
    Empty VirtualNetworkSpecSize = 8
)

These declarations collide and the embedded functions that imports a type from this api group will fail:

crossplane: error: failed to build function "firewall": failed to build runtime images: failed to build function: build: go build: exit status 1: # dev.crossplane.io/models/io/example/azure/v1alpha1
../../schemas/go/io/example/azure/v1alpha1/virtualnetwork.go:109:2: Empty redeclared in this block
    ../../schemas/go/io/example/azure/v1alpha1/subnet.go:91:2: other declaration of Empty
../../schemas/go/io/example/azure/v1alpha1/virtualnetwork.go:115:7: invalid case Empty in switch on e (mismatched types SubnetSpecSize and VirtualNetworkSpecSize)

Expected behavior: Go model generation should generate unique constant names so resources in the same package compile successfully.

How can we reproduce it?

Use a Crossplane project with Go schema generation enabled (spec.schemas.languages: ["go"]) and an embedded Go function that imports the generated API package.

Create apis/subnets/definition.yaml:

---
apiVersion: apiextensions.crossplane.io/v2
kind: CompositeResourceDefinition
metadata:
  name: subnets.example.io
spec:
  scope: Namespaced
  group: example.io
  names:
    kind: Subnet
    plural: subnets
  versions:
    - name: v1alpha1
      served: true
      referenceable: true
      schema:
        openAPIV3Schema:
          type: object
          properties:
            spec:
              type: object
              properties:
                size:
                  type: integer
                  enum: [8, 16, 32, 64, 128, 256, 512]

Create apis/virtualnetworks/definition.yaml:

---
apiVersion: apiextensions.crossplane.io/v2
kind: CompositeResourceDefinition
metadata:
  name: virtualnetworks.example.io
spec:
  scope: Namespaced
  group: example.io
  names:
    kind: VirtualNetwork
    plural: virtualnetworks
  versions:
    - name: v1alpha1
      served: true
      referenceable: true
      schema:
        openAPIV3Schema:
          type: object
          properties:
            spec:
              type: object
              properties:
                size:
                  type: integer
                  enum: [8, 16, 32, 64, 128, 256, 512]

Run crossplane project build.

Observe the duplicate Empty constants and resulting Go compilation errors.

What environment did it happen in?

Crossplane CLI version: v2.5.0
Platform: linux/amd64
Crossplane version: v2.4.2 (the failure occurs locally during the CLI build)