Support opensearch-sql:run and update developer_guide doc

[penghuo]

Description

1. Support opensearch-sql:run
2. Update developer_guide doc. add prometheus and filesystem description.
3. Add .java-version to .gitignore

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

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.
For more information on following Developer Certificate of Origin and signing off your commits, please check here.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 95.78%. Comparing base (42143b9) to head (e52d905).
⚠️ Report is 472 commits behind head on 2.x.

❌ Your project status has failed because the head coverage (95.78%) is below the target coverage (99.00%). You can increase the head coverage or adjust the target coverage.

Additional details and impacted files

@@             Coverage Diff              @@
##                2.x    #1099      +/-   ##
============================================
- Coverage     98.29%   95.78%   -2.52%     
  Complexity     3465     3465              
============================================
  Files           347      357      +10     
  Lines          8645     9303     +658     
  Branches        550      669     +119     
============================================
+ Hits           8498     8911     +413     
- Misses          142      334     +192     
- Partials          5       58      +53     

Flag	Coverage Δ
query-workbench	62.76% <ø> (?)
sql-engine	98.29% <ø> (ø)

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[dai-chen]

Thanks for the changes!