Fix LabelSelector validation markers for map field

[danehans]

Backport of PR #1679

• Fix LabelSelector validation markers for map field

  Changed MinItems/MaxItems to MinProperties/MaxProperties for the MatchLabels field in LabelSelector, as it is a map type, not an array. This resolves controller-gen CRD generation errors.

• Add CRD generation to make generate target

Add controller-gen crd to the generate target to validate kubebuilder markers during development and CI runs.

Previously, make generate only ran controller-gen object, which generates DeepCopy methods but does not validate CRD markers like MinItems, MaxItems, MinProperties, etc. This meant invalid markers could be merged without detection, only to cause failures in downstream projects that run full CRD generation.

By adding CRD generation to the generate target:

• Invalid kubebuilder markers are caught immediately during development
• CI will fail if markers are incorrect or CRDs are out of sync
• Prevents downstream projects from encountering CRD generation errors
• Aligns with the target's existing documentation which states it generates CustomResourceDefinition objects

This change would have caught the MinItems/MaxItems issue fixed in commit 40cecfd before it was merged.

• Regenerate CRDs with updated validation markers

This regenerates the CRDs to include the MinProperties/MaxProperties validation for the MatchLabels map field.

The generated CRD now includes:

• minProperties: 1
• maxProperties: 64

These properties correctly validate the map field, replacing the incorrect MinItems/MaxItems markers that were causing controller-gen failures.

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[k8s-ci-robot]

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[nirrozenbaum]

/lgtm

[danehans]

--- FAIL: TestFlowRegistry_GarbageCollection_IdleFlows (0.03s) --- FAIL: TestFlowRegistry_GarbageCollection_IdleFlows/ShouldNotCollectFlow_WhenActivityRacesWithGC (0.00s) registry_test.go:605:	Error Trace:	/home/prow/go/src/sigs.k8s.io/gateway-api-inference-extension/pkg/epp/flowcontrol/registry/registry_test.go:185	/home/prow/go/src/sigs.k8s.io/gateway-api-inference-extension/pkg/epp/flowcontrol/registry/registry_test.go:605	Error:	Received unexpected error:	failed to get managed queue for flow "gc-flow:10": flow instance not found	Test:	TestFlowRegistry_GarbageCollection_IdleFlows/ShouldNotCollectFlow_WhenActivityRacesWithGC	Messages:	Flow should survive GC due to the 'Trust but Verify' live check FAIL coverage: 97.2% of statements FAIL	sigs.k8s.io/gateway-api-inference-extension/pkg/epp/flowcontrol/registry	0.502s

/retest