Import-agent gateway creation failed with lambda (ValidationException) when calling the CreateGatewayTarget operation

**Describe the bug**
We looked through the utility of import-agent and tried to migrate agents.
I was able to migrate simple agents but the moment I went on to enable "gateway", it started throwing errors.
It was trying to create the gateway and failing while creating a lambda function or was looking for a lambda function whose name included "gateway_proxy". The error was something like the following:

`Observability enabled for gateway/history-agent-gateway-c7a5c-gdsoorkeli - logs: True, traces: True
2026-02-19 18:17:07,265 - bedrock_agentcore.gateway - INFO - ✅ Observability enabled for gateway
history-agent-gateway-c7a5c-gdsoorkeli
2026-02-19 18:17:07,266 - bedrock_agentcore.gateway - INFO - Log group:
/aws/vendedlogs/bedrock-agentcore/gateway/APPLICATION_LOGS/history-agent-gateway-c7a5c-gdsoorkeli
2026-02-19 18:17:18,358 - bedrock_agentcore.gateway - INFO - Creating Target
2026-02-19 18:17:18,358 - bedrock_agentcore.gateway - INFO - {'gatewayIdentifier': 'history-agent-gateway-c7a5c-gdsoorkeli',
'name': 'history-actions', 'targetConfiguration': {'mcp': {'lambda': {'lambdaArn':
'arn:aws:lambda:us-west-2:019598935558:function:gateway_proxy_02e1b907', 'toolSchema': {'inlinePayload': [{'name':
'history_actions_gethistoricalinfo', 'description': 'Get historical information about events, figures, or periods\\nThis tool
is part of the group of tools called history_actions.', 'inputSchema': {'type': 'object', 'properties': {'query': {'type':
'string', 'description': 'The historical query'}}, 'required': ['query']}}]}}}}, 'credentialProviderConfigurations':
[{'credentialProviderType': 'GATEWAY_IAM_ROLE'}]}
╭──────────────────────────────────────────────────── Translation Error ─────────────────────────────────────────────────────╮
│ Failed to translate agent! │
│ Error: An error occurred (ValidationException) when calling the CreateGatewayTarget operation: Lambda function not found: │
│ arn:aws:lambda:us-west-2:019598935558:function:gateway_proxy_02e1b907. Verify the function ARN is correct and retry. │
╰────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╯`

**To Reproduce**
Steps to reproduce the behavior:
1. Install package with 'agentcore starter toolkit'
2. Run command 'agentcore import-agent' in cli, with --disable-code-interpreter flag
3. See error

**Expected behavior**
Bedrock agent should be migrated to agentcore runtime with action groups translated to gateway targets

**Error Output**
```
Pasted as part of description
```

**Environment:**
- OS: [e.g. Ubuntu 22.04, macOS 13.0, Windows 11]: macOs 13.0
- Python version: [e.g. 3.10.5] 3.14
- Package version: [e.g. 0.1.0] latest
- Installation method: [pip, conda, from source] npm, pip

**Additional context**
Add any other context about the problem here.

Start with the `agentcore import-agent` CLI path and reproduce the failure using the command and `--disable-code-interpreter` flag described in the issue. Trace gateway target creation and the referenced Lambda ARN; done means action groups migrate successfully to gateway targets without the CreateGatewayTarget ValidationException.

Written by the indexing model from the issue text.