Add IP Ranges to VDN CRD, as well as additional CEL markers

[ammujumdar-bcom]

Add IP Ranges to VsphereDistributedNetwork CRD, as well as the following fields and CEL markers:

• Network Mode Type (workload vs Management)
• Ensure that IP Assignment Mode, Gateway, and subnet mask are either an IPv4 string OR empty
• Require that IP Assignment Mode, Gateway, and subnet mask are set if mode is static, OR empty if mode is DHCP
• Require that Network Name is DNS 1123 Subdomain
• Ensure that IP Assignment Mode enum is either DHCP, static, or none, and default to static
• Ensure that IP Assignment Mode field is immutable on updates

Note that these changes should be backward compatible, since the new fields are optional, and any CEL markers just enforce the already written expected behavior.

To test, verified that make generate-manifests works properly.

also ran:

/Users/ammujumdar/net-operator-api/hack/tools/bin/golangci-lint-kal run --config /Users/ammujumdar/net-operator-api/hack/.golangci-kal.yml  ./api/...
0 issues.