Overlay: Lower size limit for overlay base databases

[kaspersv]

This PR lowers the size limit for overlay base databases due to expected overlay base reductions from evaluator improvements. The change only affects overlay analysis which is currently under feature flags. The size limit functionality itself has been tested in production.

Risk assessment

For internal use only. Please select the risk level of this change:

• Low risk: Changes are fully under feature flags, or have been fully tested and validated in pre-production environments and are highly observable, or are documentation or test only.

Merge / deployment checklist

• Confirm this change is backwards compatible with existing workflows.
• Consider adding a changelog entry for this change.
• Confirm the readme and docs have been updated if necessary.

[Copilot]

Pull Request Overview

This PR reduces the maximum upload size limit for overlay base databases from 15 GB to 7.5 GB (uncompressed). This change is motivated by expected reductions in overlay base database sizes from evaluation improvements and only affects overlay analysis, which is currently behind feature flags.

Key changes:

• Updated the OVERLAY_BASE_DATABASE_MAX_UPLOAD_SIZE_MB constant from 15000 to 7500
• Updated documentation to reflect the new 3 GB compressed size estimate (down from 6 GB)

Reviewed Changes

Copilot reviewed 13 out of 13 changed files in this pull request and generated no comments.

File	Description
src/overlay-database-utils.ts	Source file containing the constant definition and updated documentation
lib/*.js	Generated JavaScript files reflecting the constant change from the TypeScript source