feat(jobs): step qty gate + partial-qty + display rename

Three coupled shop-floor corrections:
- fp.job._compute_display_name: renders "Work Order # 00011" in
  form header, breadcrumbs, M2O dropdowns, and error messages.
  DB name stays as WH/JOB/00011 - existing chatter/cert/delivery
  references unchanged.
- fp.job.step.button_finish: refuses if qty_at_step > 0 AND a
  downstream pending/ready step exists. Last runnable step is
  exempt (parts complete in place). Manager bypass via
  fp_skip_qty_gate=True context key.
- fp.job.step.action_complete_one_to_next: new per-row button
  "Complete 1 -> Next" for streaming flow (large parts going
  one-by-one). Records move(qty=1) to next step; if drain takes
  qty_at_step to 0, auto-finishes source + auto-starts destination
  via existing action_finish_and_advance.
- fp.job.step._fp_record_one_piece_auto_move: auto-move shim
  wired into action_finish_and_advance. qty=1 + downstream =>
  silently record move(1). qty>1 + downstream => raise pointing
  at Complete 1 -> Next. Last step always allowed.
- 16 new TestQtyGate tests covering gate / shim / auto-finish /
  last-step exemption / display rename / Move wizard zero-qty.

Spec: docs/superpowers/specs/2026-05-12-step-qty-gate-and-display-rename-design.md
Plan: docs/superpowers/plans/2026-05-12-step-qty-gate-and-display-rename.md

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

fusion_plating/fusion_plating/views/fp_job_views.xml

@@ -35,7 +35,7 @@
                 </header>
                 <sheet>
                     <div class="oe_title">
-                        <h1><field name="name" readonly="1"/></h1>
+                        <h1><field name="display_name" readonly="1"/></h1>
                     </div>
                     <group>
                         <group>