Get Shared Project

Get metadata for a shared project (read-only, no side effects).

This is the primary entry point for shared project access. Validates the share token and returns project metadata. View count tracking is handled separately via POST /{share_token}/view.

Args: share: Validated ProjectShare from token (injected by validate_share_token) share_service: ProjectShareService for fetching project data

Returns: Shared project metadata (subset of full project data)

Raises: HTTPException: 404 if project not found