Extend OH SQL for snapshots retention

[teamurko]

Summary

Support configurable snapshots retention (SQL, PR1)

• time-based retention, supported hour and day granularity
• count-based retention, the most recent N are preserved when expiring snapshots

Next:

• Handle snapshotsRetention property
• Propagate the policy to ES app

Changes

• [x] Client-facing API Changes
• [ ] Internal API Changes
• [ ] Bug Fixes
• [x] New Features
• [ ] Performance Improvements
• [ ] Code Style
• [ ] Refactoring
• [ ] Documentation
• [ ] Tests

For all the boxes checked, please include additional details of the changes made in this pull request.

Testing Done

• [x] Manually Tested on local docker setup. Please include commands ran, and their output.
• [x] Added new tests for the changes made.
• [ ] Updated existing tests to reflect the changes made.
• [ ] No tests added or updated. Please explain why. If unsure, please feel free to ask for help.
• [ ] Some other form of testing like staging or soak time in production. Please explain.

For all the boxes checked, include a detailed description of the testing done for the changes made in this pull request.

Additional Information

• [ ] Breaking Changes
• [ ] Deprecations
• [ ] Large PR broken into smaller PRs, and PR plan linked in the description.

For all the boxes checked, include additional details of the changes made in this pull request.