Add structured_metadata support to the output of chunks-inspect cli

[gonzalesraul]

Is your feature request related to a problem? Please describe.

The https://github.com/grafana/loki/tree/main/cmd/chunks-inspect allow to print some useful information about chunks directly, however the current implementation does not support v13 which comes with the structured metadata stored.

Describe the solution you'd like

Ideally the output could print the non-indexed information stored that comes as part of structured metadata.

Describe alternatives you've considered
There is no other tool available to describe data stored in chunks files

Additional context

While dealing with the alpha structured metadata feature, there was an issue that I've stumbled #10683 which shows that is not clear a way to verify if the data was stored as non-indexed information. Having this as part of that tooling will help a lot verify more of the chunk structure