Plan task P1.2. Reuses _fp_should_block_predecessors so the new compute
stays in sync with the existing can_start logic. Drives the OWL GateViz
component on the tablet — "Can't start yet — Waiting on Step N: X".
Future work: extend with explicit branches for contract_review /
parts_not_received / racking_required / manager_input as those gate
models mature.
Tests not run locally (no fusion_plating mount in odoo-modsdev).
Verify on entech: -u fusion_plating_jobs --test-tags fp_jobs.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>