DynamoDB Mapper generated types should propagate docs from low-level types

[ianbotsf]

Describe the bug

The generated wrappers for DDB Mapper high-level operations and types currently contain sparse documentation but, in most cases, they wrap low-level ops/types which contain the right documentation already. We should propagate docs appropriately so that its easier for users to understand the high-level types.

Regression Issue

• Select this option if this issue appears to be a regression.

Expected behavior

High-level wrapper operations and types contain proper documentation

Current behavior

High-level wrapper operations and types do not contain proper documentation

Steps to Reproduce

Look at the KDocs for the high-level operations and types

Possible Solution

No response

Context

No response

AWS SDK for Kotlin version

any

Platform (JVM/JS/Native)

all

Operating system and version

any