[READY FOR REVIEW] Implement Database-Backed Ingestion Progress Bar

[bharatsachya]

What changed

• Created DbProgressReporter: Added DbProgressReporter.ts to track, throttle (250ms), and write real-time ingestion progress to MongoDB or SQLite via the knowledgeDb abstraction.
• Defaulted Worker Configuration: Configured the ingestion workers in packages/ingest-github/src/index.ts to use dbProgressContextFactory by default, keeping public registration signatures clean and localized.
• Improved UI Liveness: Prevented the progress bar from resetting to 0% after the file analysis phase completes (during folder analysis and database indexing phases) by maintaining the progress at 100% of analyzed files.
• Fixed File Count Display: Updated reposRoute.ts in the server to fall back to status.totalFiles for reporting the fileCount value, ensuring the CLI prints the correct number of files indexed (e.g. 17 files) rather than 0 files upon completion.

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Why

The CLI depends on polling the server's repos REST endpoint to show progress and file counts. However, since the open-source client clones to disk directly and does not write raw file archives to the database, fileCount returned 0 and progress fields stayed undefined (because workers defaulted to nullProgressContextFactory).

This PR resolves both issues without requiring any changes to public registration APIs or server-boot configurations.

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How to test

1. Boot up the backend infrastructure and the server:

   bun run bytebell boot

bytebell index repo

[bharatsachya]

Against #66