feat(fusion_plating_jobs): late_risk_ratio + active_step_id computes on fp.job

Plan tasks P2.2 + P2.3 batched (both small additive computes on fp.job;
local tests not run between them — entech verifies).

  late_risk_ratio  — stored Float, remaining_planned / minutes_to_deadline.
                     Drives the Manager At-Risk view (Phase 4).
                     Recomputes on step state, duration, deadline changes.

  active_step_id   — non-stored Many2one. Currently in_progress step
                     (lowest sequence if multiple — defensive).
                     Drives JobWorkspace landing focus.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

fusion_plating/fusion_plating_jobs/tests/__init__.py

@@ -4,3 +4,5 @@ from . import test_fp_job_milestone_cascade
 from . import test_qty_received_propagation
 from . import test_display_wo_name
 from . import test_blocker_compute
+from . import test_late_risk_ratio
+from . import test_active_step_id