[FEATURE]Add REPL & language validator

[YANG-DB]

Is your feature request related to a problem?

This third step of consolidating the PPL spec into a single repository which will be deployed as an independent artifact.

What solution would you like?

Third step:

• Create a self container REPL testing artifact for anyone to experiment with the grammar - REPL is a tool that parses, analyzes, and executes PPL queries using the reference implementation, providing users with an interactive environment to test and run PPL queries seamlessly.
• Create an ANTLR based polyglot validator artifact library that can also be imported by any 3rd party
  • Java validator
  • J/S validator
  • Python validator

#23 - Main RFC

Do you have any additional context?

• https://github.com/opensearch-project/sql/tree/main/ppl/src/main/antlr
• https://github.com/opensearch-project/sql/tree/main/ppl/src/main/java/org/opensearch/sql/ppl
• https://github.com/opensearch-project/opensearch-spark/tree/main/ppl-spark-integration/src/main/java/org/opensearch/sql/ast
• https://github.com/opensearch-project/opensearch-spark/tree/main/ppl-spark-integration/src/main/antlr4