feat: Add NetworkType + IPDiscovery to ReplicationGroup (#179)

Issue [#2565](aws-controllers-k8s/community#2565)

Description of changes:
* support NetworkType + IPDiscovery
* add unit tests

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

Author: michaelhtm

apis/v1alpha1/ack-generate-metadata.yaml

@@ -1,13 +1,13 @@
 ack_generate_info:
-  build_date: "2025-07-23T02:15:05Z"
-  build_hash: b2dc0f44e0b08f041de14c3944a5cc005ba97c8f
+  build_date: "2025-08-08T21:25:54Z"
+  build_hash: b4fbf4e427daaef74ed873aac01e4a9ca68fb479
   go_version: go1.24.5
-  version: v0.50.0
-api_directory_checksum: cd3855ca5e9598e4a45cdc8b295054981b08dbb7
+  version: v0.50.0-3-gb4fbf4e
+api_directory_checksum: 5a16cea62c98405d3786f1ee1aad22ff3fafc7d6
 api_version: v1alpha1
 aws_sdk_go_version: v1.32.6
 generator_config_info:
-  file_checksum: d70e645a0a1ac78d523b7ff0b09ccbfd9bbbfb96
+  file_checksum: a3aa9d437d76c0a739168005043783103bf199da
   original_file_name: generator.yaml
 last_modification:
   reason: API generation

apis/v1alpha1/generator.yaml

@@ -178,7 +178,8 @@ resources:
       PrimaryClusterId: # note: "PrimaryClusterID" will not function properly
         compare:
           is_ignored: true
-      
+      NetworkType:
+        is_immutable: true
     hooks:
       sdk_read_many_post_set_output:
         template_path: hooks/replication_group/sdk_read_many_post_set_output.go.tpl
@@ -426,11 +427,5 @@ ignore:
     - CreateReplicationGroupInput.ClusterMode
     - ModifyReplicationGroupOutput.ReplicationGroup.ClusterMode
     - ModifyReplicationGroupOutput.ReplicationGroup.PendingModifiedValues.ClusterMode
-    - CreateReplicationGroupInput.IpDiscovery
-    - CreateReplicationGroupOutput.ReplicationGroup.IpDiscovery
     - Subnet.SupportedNetworkTypes
     - CreateReplicationGroupInput.ServerlessCacheSnapshotName
-    - CreateReplicationGroupOutput.ReplicationGroup.NetworkType
-    - CreateReplicationGroupInput.NetworkType
-    # - ModifyReplicationGroupOutput.ReplicationGroup.ipDiscovery
-    # - ModifyReplicationGroupInput.ipDiscovery

apis/v1alpha1/replication_group.go

@@ -250,6 +250,13 @@ spec:
                   existing cluster or replication group and create it anew with the earlier
                   engine version.
                 type: string
+              ipDiscovery:
+                description: |-
+                  The network type you choose when creating a replication group, either ipv4
+                  | ipv6. IPv6 is supported for workloads using Valkey 7.2 and above, Redis
+                  OSS engine version 6.2 and above or Memcached engine version 1.6.6 and above
+                  on all instances built on the Nitro system (http://aws.amazon.com/ec2/nitro/).
+                type: string
               kmsKeyID:
                 description: The ID of the KMS key used to encrypt the disk in the
                   cluster.
@@ -294,6 +301,16 @@ spec:
                   A flag indicating if you have Multi-AZ enabled to enhance fault tolerance.
                   For more information, see Minimizing Downtime: Multi-AZ (http://docs.aws.amazon.com/AmazonElastiCache/latest/dg/AutoFailover.html).
                 type: boolean
+              networkType:
+                description: |-
+                  Must be either ipv4 | ipv6 | dual_stack. IPv6 is supported for workloads
+                  using Valkey 7.2 and above, Redis OSS engine version 6.2 and above or Memcached
+                  engine version 1.6.6 and above on all instances built on the Nitro system
+                  (http://aws.amazon.com/ec2/nitro/).
+                type: string
+                x-kubernetes-validations:
+                - message: Value is immutable once set
+                  rule: self == oldSelf
               nodeGroupConfiguration:
                 description: |-
                   A list of node group (shard) configuration options. Each node group (shard)