Adds plan context for Scroll physical plan building

[seankao-az]

Description

1. Adds plan context that can be modified during request handling and/or logical plan analysis. It is then used to help build the physical plan. Right now it has only one field, namely, IndexScanMode, IndexScanType, which decides whether to invoke a regular query request or a scroll request to OpenSearch.
   Before:
   logical plan => physical plan
   After:
   (logical plan, plan context) => physical plan
   An example use case is to distinguish scrolling requests from regular query requests ([FEATURE] - Support pagination for PPL and SQL query #656) . Both of them can have the exact same query, and therefore, have the exact same logical plan. They differ only in the underlying index scan operator choice.
   We can set the index scan type to SCROLL during request handling.
   Another use case is to allow for some commands to request more data rows than query.size_limit and index.max_result_window (Extend size_limit setting in query engine to support unlimited index query. #703).

2. Pull opensearch index scan results in batches, rather than loading all at once.

Issues Resolved

This is a building block for both #656 and #703

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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[codecov-commenter]

Codecov Report

Merging #713 (3fade3c) into main (592c58b) will decrease coverage by 31.98%.
The diff coverage is n/a.

@@              Coverage Diff              @@
##               main     #713       +/-   ##
=============================================
- Coverage     94.74%   62.76%   -31.99%     
=============================================
  Files           283       10      -273     
  Lines          7676      658     -7018     
  Branches        560      118      -442     
=============================================
- Hits           7273      413     -6860     
+ Misses          349      192      -157     
+ Partials         54       53        -1     

Flag	Coverage Δ
query-workbench	62.76% <ø> (ø)
sql-engine	?

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Impacted Files	Coverage Δ
...a/org/opensearch/sql/analysis/AnalysisContext.java
.../main/java/org/opensearch/sql/planner/Planner.java
...rc/main/java/org/opensearch/sql/storage/Table.java
...search/sql/opensearch/storage/OpenSearchIndex.java
...ch/sql/opensearch/storage/OpenSearchIndexScan.java
...ensearch/storage/system/OpenSearchSystemIndex.java
...c/main/java/org/opensearch/sql/ppl/PPLService.java
...c/main/java/org/opensearch/sql/sql/SQLService.java
...n/java/org/opensearch/sql/utils/OperatorUtils.java
...opensearch/executor/OpenSearchExecutionEngine.java
... and 263 more

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[seankao-az]

The PlanContext isn't that useful compared to its added complexity to the overall design