Format Java code automatically and enforce it in Solr

See the discussion at: LUCENE-9564.

This is a placeholder for the present, I'm reluctant to do this to the Solr code base until after:

• we have some Solr-specific consensus
• we have some clue what this means for the reference impl.

Reconciling the reference impl will be difficult enough without a zillion format changes to add to the confusion.

So my proposal is

1> do this.

2> Postpone this until after the reference impl is merged.

3> do this in one single commit for reasons like being able to conveniently have this separated out from git blame.

Assigning to myself so it doesn't get lost, but anyone who wants to take it over please feel free.