PoC Refactor: Move relevance search functions from :core to :opensearch

[Yury-Fridlyand]

Description

Phase 2 of UDF (User Defined Function) implementation
(See phase 1 in #2019)

Depends on #2001 (a rough fix for that is included in this PR, but it should be merged in scope of another PR in advance.
Fix proposed in #2002 could be done prior to these changes to simplify the refactor.

These changes include:

• All opensearch specific code was moved from :core to :opensearch
• OpenSearch specific analyzers were moved too
• StorageEngine provides API to get DS-specific analyzers, which is used by analyzer in :core (common to all DS)

TODOs:

• Complete TODOs left in code
• Make Analyzers and CanPaginateVisitor abstract, every DS should provide their own implementation

Next Steps (phases):

• In the current state, code checks for DS analyzers if common analyzer meets something unknown (DS-specific). It means that analyzers from different DS may be invoked during processing a single query.
  SQL engine should try to execute a query on all StorageEngines (Data Sources), using only one StorageEngine from the very beginning to the very end (QueryPlanFactory - ExecutionEngine::execute) and pick one which succeeds to build a Physical Plan tree.
  TBD: what if multiple StorageEngines can build a tree?
  Note: reuse common parts for better performance.
  important: this could be moved to the next phase if current one would be implemented with not more that one DS.
• Let DS have their own parsers, free SQL and PPL parsers from DS-specific stuff.
• Move Prometheus to another DS
• Extend config to allow configuring DS list (and their parameters) before starting the cluster
• Extend DS management API to plug-in/out DS with their UDF in runtime
• Improve identifier resolution strategy per DS

Issues Resolved

P2 of #811

Check List

• New functionality includes testing.
  • All tests pass, including unit test, integration test and doctest
• New functionality has been documented.
  • New functionality has javadoc added
  • New functionality has user manual doc added
• Commits are signed per the DCO using --signoff

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