Support client-side encryption for S3 uploads

[andresC98]

Describe the feature or potential improvement

Even though S3 data at rest encryption is supported at server-side outside Langfuse (via e.g. AWS KMS), it would be nice for Langfuse to support encryption at client side so that data sent to S3 or any generic Object Store is encrypted at client side.

Additional information

No response

[Steffen911]

@andresC98 Currently, there are no active plans to support this, but we would consider community contributions to our StorageService implementation to include this.