[logging] add a maximum size to structured logging
[logging] add a maximum size to structured logging

The autoconverted structured logging lines are causing there to be too
much data that's getting cut off.  This limits the amount of data in a
log line to ensure delivery, adding an error message to know if we need
to shrink the size of the line.

Closes: #5267
Approved by: andll

libra/libra,aptos-labs/aptos-core,aptos-labs/aptos-core,libra/libra,aptos-labs/aptos-core,aptos-labs/aptos-core,libra/libra,aptos-labs/aptos-core,aptos-labs/aptos-core,libra/libra,aptos-labs/aptos-core,libra/libra