[Feature Request] Add GitHub Projects v2 Status Field Sync Support

## Summary

Add support for syncing the "Status" custom field from GitHub Projects v2 to Huly issue statuses, enabling true bi-directional status synchronization.

## Current Behavior

- Huly syncs GitHub Issue state (`open`/`closed`) but not GitHub Projects v2 custom fields
- When a user moves an issue to "In Progress" on a GitHub Project board, the status doesn't update in Huly
- When a user changes status in Huly, the GitHub Project board position doesn't change
- All synced issues appear as "Backlog" (open) or "Done" (closed) regardless of their Project board column

## Expected Behavior

- Huly should read the "Status" field from GitHub Projects v2 and map it to corresponding Huly issue statuses
- Status changes in Huly should update the GitHub Project's Status field
- Allow users to configure status mapping (e.g., GitHub "Ready" → Huly "Todo")

## Use Case

Our organization uses GitHub Projects v2 for sprint planning with statuses: Backlog, Ready, In Progress, In Review, Done. We want to use Huly as our primary project management tool while keeping GitHub Projects in sync for developers who prefer staying in GitHub.

## Technical Context

GitHub Projects v2 uses the GraphQL API with `ProjectV2ItemFieldSingleSelectValue` for status fields. The current integration appears to only use the REST API for issue state.

## Environment

- Huly Version: 0.7.342 (self-hosted)
- GitHub: Organization with Projects v2

## Related

This would make the GitHub integration significantly more valuable for teams migrating from GitHub-centric workflows.