Allow Build Insights users to re-submit individual Helix jobs and work items

### Problem
Currently, there is no way for Build Insights users to manually re-run or re-submit individual Helix jobs. The only mechanism that exists today is the automatic `BuildRetry` option configured via known issue JSON (e.g., [dotnet/dnceng#6408](https://github.com/dotnet/dnceng/issues/6408)), which re-runs the entire AzDO build. There is no way to target a specific Helix job for re-submission.

### Proposed Solution
- **Phase 1 – Re-submit individual Helix jobs:** Give Build Insights users the ability to re-submit a specific Helix job without re-running the entire AzDO build.
- **Phase 2 – Re-submit individual work items:** Investigate extending this to allow re-running individual work items within a Helix job (each Helix job contains one or more work items).

### Expected Outcomes
- Users can selectively re-submit failed or flaky Helix jobs directly from Build Insights.
- Eliminates the need to re-run entire AzDO builds just to retry a single Helix job.
- Significantly reduces wasted compute time and shortens feedback loops for developers.
- At work-item granularity, users gain even finer control over what gets re-executed.

### Impact
This would be a huge quality-of-life win for users who rely on Helix test infrastructure. Today, a single flaky Helix job can force an entire build re-run (via `BuildRetry`), wasting significant time and resources across the ecosystem.