fix(iam): Role.addManagedPolicy() does not work for imported roles IRole #8307 (#31212)

### Issue #8307

Closes #8307

### Reason for this change
- This addManagedPolicy() just does nothing, neither throws warning nor
fails.

### Description of changes
- This implements **addManagedPolicy()** for **ImportedRole**
- This throws Error, when `IRole` is used with `IManagedPolicy`, due to
constrains

### Approaches decided
- we can't change **addManagedPolicy(policy: IManagedPolicy)** to
**addManagedPolicy(policy: ManagedPolicy)** (i.e., to ManagedPolicy) ,
like how **attachInlinePolicy(policy: Policy)**, it will break for
almost many customers.
-
https://github.com/aws/aws-cdk/blob/823ff6e03899f790a4cb1c43f92a02cc906ac356/packages/aws-cdk-lib/aws-iam/lib/identity-base.ts#L17-L21
- So, we need to handle this gracefully when accepting only
**ManagedPolicy**.
- We can't use IRole & IManagedPolicy to do the work at the same time,
so we need to allow ManagedPolicy in params, and throw Error when
IManagedPolicy is being sent, because of how **attachToRole()** will be
used by **addManagedPolicy()**
- #### This PR Implements follows,
  - enables **addManagedPolicy()**
  - Accepts **ManagedPolicy**
- Throws understandable Error, when `IRole` is used with
`IManagedPolicy`.

### Description of how you validated changes
- unit & integration tests

### Checklist
- [x] My code adheres to the [CONTRIBUTING
GUIDE](https://github.com/aws/aws-cdk/blob/main/CONTRIBUTING.md) and
[DESIGN
GUIDELINES](https://github.com/aws/aws-cdk/blob/main/docs/DESIGN_GUIDELINES.md)

----

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

---------

Co-authored-by: paulhcsun <[email protected]>
Co-authored-by: GZ <[email protected]>

Author: 3 people

packages/@aws-cdk-testing/framework-integ/test/aws-iam/test/integ.imported-role.js.snapshot/ImportedRoleTestAssertions.assets.json

@@ -34,7 +34,7 @@
      "PolicyNames.2",
      "PolicyNames.3"
     ],
-    "salt": "1697413484207"
+    "salt": "1729447009370"
    },
    "UpdateReplacePolicy": "Delete",
    "DeletionPolicy": "Delete"
@@ -73,6 +73,15 @@
          "Resource": [
           "*"
          ]
+        },
+        {
+         "Action": [
+          "iam:ListAttachedRolePolicies"
+         ],
+         "Effect": "Allow",
+         "Resource": [
+          "*"
+         ]
         }
        ]
       }
@@ -83,12 +92,20 @@
   "SingletonFunction1488541a7b23466481b69b4408076b81HandlerCD40AE9F": {
    "Type": "AWS::Lambda::Function",
    "Properties": {
-    "Runtime": "nodejs18.x",
+    "Runtime": {
+     "Fn::FindInMap": [
+      "LatestNodeRuntimeMap",
+      {
+       "Ref": "AWS::Region"
+      },
+      "value"
+     ]
+    },
     "Code": {
      "S3Bucket": {
       "Fn::Sub": "cdk-hnb659fds-assets-${AWS::AccountId}-${AWS::Region}"
      },
-     "S3Key": "c91921c142e824b74d06797a2be74eab5d0dd0453e753549f5182ac7a02f556b.zip"
+     "S3Key": "e77649078c9dea5bbb707b7fe68014cfa5d919a38d31b467f6a205b51ea63a83.zip"
     },
     "Timeout": 120,
     "Handler": "index.handler",
@@ -99,6 +116,43 @@
      ]
     }
    }
+  },
+  "AwsApiCallIAMlistAttachedRolePolicies7b6e565f3b40bc5c7faa65c17a68f5be": {
+   "Type": "Custom::DeployAssert@SdkCallIAMlistAttachedRolePolicies",
+   "Properties": {
+    "ServiceToken": {
+     "Fn::GetAtt": [
+      "SingletonFunction1488541a7b23466481b69b4408076b81HandlerCD40AE9F",
+      "Arn"
+     ]
+    },
+    "service": "IAM",
+    "api": "listAttachedRolePolicies",
+    "expected": "{\"$StringLike\":\"^MyCustomManagedPolicy[0-9]$\"}",
+    "actualPath": "AttachedPolicies.1.PolicyName",
+    "parameters": {
+     "RoleName": {
+      "Fn::Join": [
+       "",
+       [
+        "\"",
+        {
+         "Fn::ImportValue": "integ-iam-imported-role-3:ExportsOutputRefroleToBeImportedCAC1213CDE38D2C6"
+        },
+        "\""
+       ]
+      ]
+     }
+    },
+    "flattenResponse": "true",
+    "outputPaths": [
+     "AttachedPolicies.0.PolicyName",
+     "AttachedPolicies.1.PolicyName"
+    ],
+    "salt": "1729447009371"
+   },
+   "UpdateReplacePolicy": "Delete",
+   "DeletionPolicy": "Delete"
   }
  },
  "Outputs": {
@@ -109,6 +163,138 @@
      "assertion"
     ]
    }
+  },
+  "AssertionResultsAwsApiCallIAMlistAttachedRolePolicies7b6e565f3b40bc5c7faa65c17a68f5be": {
+   "Value": {
+    "Fn::GetAtt": [
+     "AwsApiCallIAMlistAttachedRolePolicies7b6e565f3b40bc5c7faa65c17a68f5be",
+     "assertion"
+    ]
+   }
+  }
+ },
+ "Mappings": {
+  "LatestNodeRuntimeMap": {
+   "af-south-1": {
+    "value": "nodejs20.x"
+   },
+   "ap-east-1": {
+    "value": "nodejs20.x"
+   },
+   "ap-northeast-1": {
+    "value": "nodejs20.x"
+   },
+   "ap-northeast-2": {
+    "value": "nodejs20.x"
+   },
+   "ap-northeast-3": {
+    "value": "nodejs20.x"
+   },
+   "ap-south-1": {
+    "value": "nodejs20.x"
+   },
+   "ap-south-2": {
+    "value": "nodejs20.x"
+   },
+   "ap-southeast-1": {
+    "value": "nodejs20.x"
+   },
+   "ap-southeast-2": {
+    "value": "nodejs20.x"
+   },
+   "ap-southeast-3": {
+    "value": "nodejs20.x"
+   },
+   "ap-southeast-4": {
+    "value": "nodejs20.x"
+   },
+   "ap-southeast-5": {
+    "value": "nodejs20.x"
+   },
+   "ap-southeast-7": {
+    "value": "nodejs20.x"
+   },
+   "ca-central-1": {
+    "value": "nodejs20.x"
+   },
+   "ca-west-1": {
+    "value": "nodejs20.x"
+   },
+   "cn-north-1": {
+    "value": "nodejs18.x"
+   },
+   "cn-northwest-1": {
+    "value": "nodejs18.x"
+   },
+   "eu-central-1": {
+    "value": "nodejs20.x"
+   },
+   "eu-central-2": {
+    "value": "nodejs20.x"
+   },
+   "eu-isoe-west-1": {
+    "value": "nodejs18.x"
+   },
+   "eu-north-1": {
+    "value": "nodejs20.x"
+   },
+   "eu-south-1": {
+    "value": "nodejs20.x"
+   },
+   "eu-south-2": {
+    "value": "nodejs20.x"
+   },
+   "eu-west-1": {
+    "value": "nodejs20.x"
+   },
+   "eu-west-2": {
+    "value": "nodejs20.x"
+   },
+   "eu-west-3": {
+    "value": "nodejs20.x"
+   },
+   "il-central-1": {
+    "value": "nodejs20.x"
+   },
+   "me-central-1": {
+    "value": "nodejs20.x"
+   },
+   "me-south-1": {
+    "value": "nodejs20.x"
+   },
+   "mx-central-1": {
+    "value": "nodejs20.x"
+   },
+   "sa-east-1": {
+    "value": "nodejs20.x"
+   },
+   "us-east-1": {
+    "value": "nodejs20.x"
+   },
+   "us-east-2": {
+    "value": "nodejs20.x"
+   },
+   "us-gov-east-1": {
+    "value": "nodejs18.x"
+   },
+   "us-gov-west-1": {
+    "value": "nodejs18.x"
+   },
+   "us-iso-east-1": {
+    "value": "nodejs18.x"
+   },
+   "us-iso-west-1": {
+    "value": "nodejs18.x"
+   },
+   "us-isob-east-1": {
+    "value": "nodejs18.x"
+   },
+   "us-west-1": {
+    "value": "nodejs20.x"
+   },
+   "us-west-2": {
+    "value": "nodejs20.x"
+   }
   }
  },
  "Parameters": {