[ES|QL] Use the new structure of lexer parser from ES

[stratoula]

Describe the feature:

ES here elastic/elasticsearch#122075 breaks the lexer and parser to smaller chunks for readability. We need to:

• check that the new structure works exactly the same for kibana
• change the lexer / parser script to accommodate the new structure

[elasticmachine]

Pinging @elastic/kibana-esql (Team:ESQL)

[stratoula]

@drewdaemon I did a quick check that everything works ok. #210766

We need to set up the -lib option https://github.com/antlr/antlr4/blob/master/doc/tool-options.md to make antlr take under consideration the new folders

It seems to work as expected, I didnt find any regressions with a very brief testing.

The src/platform/packages/shared/kbn-esql-ast/scripts/fix_generated_antlr.jsis failing though and I am not sure I understand why. Do you want to add this to your list? (without changing our current priorities).

[drewdaemon]

@stratoula sure thing. And yeah I have no idea what that script does. Will look into it.

[drewdaemon]

I like that this change mirrors the refactor in #195418

[stratoula]

yeah ++