Add monitoring service and database schema

- Implement monitoring service with heartbeat, lease tasks, resume tasks, and task result handling.
- Create monitoring time utilities for business date calculations.
- Add unit tests for date window resolution and business day handling.
- Define database schema for monitoring-related tables including quotas, daily reports, and task management.
- Establish migration scripts for creating and dropping monitoring tables.

server/internal/tenant/app/monitoring_errors.go

@@ -0,0 +1,9 @@
+package app
+
+import "github.com/geo-platform/tenant-api/internal/shared/response"
+
+func monitoringInternalError(code int, message, detail string, cause error) *response.AppError {
+	appErr := response.ErrInternal(code, message, detail)
+	appErr.Cause = cause
+	return appErr
+}