Warn and skip for data-related COPY TO KV runtime errors (part 2)

The following errors can take place when writing to KV, for this list of errors, we need to warn, include the key of the problematic document in the warning, skip the writing and move to the next record.

• The key must not be longer than 250 bytes
• The document value is too large to be stored
• Sub-document path length exceeds 1024
• Sub-document path nesting level exceeds 32

list of sizing limitations:

https://docs.couchbase.com/server/current/learn/clusters-and-availability/size-limitations.html