When parsing queries on the coordinating node, there is currently no way to share state between the different parsing methods (`fromXContent`). The only query that supports a parse context is bool query, which uses the context to track nested depth of queries, added with #66204. Such nested depth tracking mechanism is not 100% accurate as it tracks bool queries only, while there's many more query types that can hold other queries hence potentially cause stack overflow when deeply nested.
This change removes the parsing context that's specific to bool query, introduced with #66204, in favour of generalizing the nested depth tracking to all query types.
The generic tracking is introduced by wrapping the parser and overriding the method that parses named objects through the xcontent registry. Another way would have been to require a context argument when parsing queries, which would mean adding a context argument to all the QueryBuilder#fromXContent static methods. That would be a breaking change for plugins that provide custom queries, hence I went for trying out a different approach.
One aspect that this change requires and introduces is the distinction between parsing a top level query (which will wrap the parser, or it would create the context if we had one), as opposed to parsing an inner query, which goes ahead with the given parser and context. We already have this distinction as we have two different static methods in `AbstractQueryBuilder` but in practice only bool query makes the distinction being the only context-aware query.
In addition to generalizing tracking nested depth when parsing queries, we should be able to adopt this same strategy to track queries usage as part #90176 .
Given that the depth check is now more restrictive, as it counts all compound queries and not only bool, we have decided to raise the default limit to `30` to ensure that users are not going to hit the limit due to this change.
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