[Build] feat: refactor KPI page and cleanup unused files

## GitHub Update **Repository:** [MKWcorp/hrisnextgen](https://github.com/MKWcorp/hrisnextgen) **Author:** multimediadrw **Date:** 10/26/2025, 11:21:14 PM **Commit:** [`e63d87f`](https://github.com/MKWcorp/hrisnextgen/commit/e63d87fe4a105bbfe98f65d3cbb132af88b981d8) ### Commit Message feat: refactor KPI page and cleanup unused files - Moved KPI page to dynamic route: /dashboard/kpis/[batch_id] - Removed KPI Approval from sidebar navigation (access via Goals/Dashboard) - Fixed BigInt serialization in assign API endpoint - Cleaned up unused documentation files and scripts - Fixed TypeScript errors in API routes (removed invalid relations) - Updated navigation links in Goals and Dashboard pages - Fixed polling mechanism for AI workflow status - Added proper error handling for KPI fetching Breaking Changes: - KPI page URL changed from /dashboard/kpis?batch_id=X to /dashboard/kpis/[batch_id] - Removed direct sidebar access to KPI page (contextual access only) --- _This story was imported from historical commits._