(aws-glue-alpha): No connection type for SNOWFLAKE

### Describe the feature

Snowflake is a native connection type in Glue now, but Glue Alpha doesn't have an option for connection.type = SNOWFLAKE. This should be supported.

### Use Case

Connecting from Glue to Snowflake easily.

### Proposed Solution

Support the native Snowflake connector

### Other Information

_No response_

### Acknowledgements

- [x] I may be able to implement this feature request
- [ ] This feature might incur a breaking change

### AWS CDK Library version (aws-cdk-lib)

2.185.0

### AWS CDK CLI version

2.128.0

### Environment details (OS name and version, etc.)

N/A

Start by locating the aws-glue-alpha implementation that defines or validates connection.type and compare its existing native connection types. Confirm how SNOWFLAKE is represented and find the relevant tests or entry points for Glue connections. Done means a Snowflake connection can be configured with connection.type = SNOWFLAKE and the relevant checks pass.

Written by the indexing model from the issue text.