feat(plating): company-level UoM defaults — F/C, mils/microns, etc.

Different facilities use different measurement systems. North-American
aerospace shops live in °F + mils + gallons + lb; ROW + most metric
shops use °C + microns + litres + kg. Add company-level defaults so
each shop picks its units once; new records inherit them automatically.

**Settings on res.company** (7 Selection fields):
  • x_fc_default_temp_uom            — °F / °C
  • x_fc_default_thickness_uom       — mils / microns / inches / mm
  • x_fc_default_volume_uom          — US gal / litres / Imp gal
  • x_fc_default_mass_uom            — lb / kg / oz / g
  • x_fc_default_pressure_uom        — psi / bar / kPa
  • x_fc_default_current_density_uom — A/ft² (ASF) / A/dm² (ASD)
  • x_fc_default_area_uom            — sq in / sq ft / cm² / m²

All default to North-American aerospace conventions (F, mils, gal, lb,
psi, asf, sq_in) — admins flip them once during onboarding via
Settings → Fusion Plating → Units of Measure.

**Per-record use** (this round)
  • mrp.workorder.x_fc_bake_temp_uom (°F / °C) — defaults from company,
    operator can override per WO if a specific bake needs a different
    unit (rare but allowed).
  • Bake-finish gate error message now reports the actual unit:
    "Bake Temp (°F)" or "Bake Temp (°C)" instead of hard-coded F.
  • Form: Bake Temp + Temp Unit picker side-by-side in the bake group.

**Settings UI** — new "Units of Measure" block on Settings → Fusion
Plating page with help text per unit explaining where each is used.

**Verified end-to-end** (scripts/fp_uom_smoke.py):
  • All 7 defaults populate with NA-aerospace defaults
  • Switching company default to °C makes a NEW WO inherit °C
  • Existing WOs keep their stored °F (no surprise mutation)

**Roadmap (deferred to next round)** — wire the same default-from-company
inheritance to:
  • fp.bake.oven.target_temp (currently no UoM)
  • fp.bake.window.bake_temp (currently no UoM)
  • fp.coating.config.bake_temperature (currently no UoM)
  • fp.tank.volume already has volume_uom; default from company
  • fp.bath.log chemistry readings already use parameter.uom; align
    with company default for new params

The settings + framework are now in place — adding more per-record uom
fields is mechanical from here.

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

fusion_plating/scripts/fp_uom_smoke.py

@@ -0,0 +1,35 @@
+env = env  # noqa
+co = env.company
+print('Company unit defaults on', co.name)
+for f in ('x_fc_default_temp_uom', 'x_fc_default_thickness_uom',
+          'x_fc_default_volume_uom', 'x_fc_default_mass_uom',
+          'x_fc_default_pressure_uom', 'x_fc_default_current_density_uom',
+          'x_fc_default_area_uom'):
+    print(f'  {f:<36} {getattr(co, f, "(missing)")}')
+
+# Switch company default to Celsius and verify a new WO inherits it
+print('\\nSwitching company default to °C...')
+co.sudo().x_fc_default_temp_uom = 'C'
+
+mo = env['mrp.production'].sudo().search([], order='id desc', limit=1)
+if mo:
+    bake_wo = mo.workorder_ids.filtered(
+        lambda w: hasattr(w, '_fp_classify_kind') and w._fp_classify_kind() == 'bake'
+    )[:1]
+    if bake_wo:
+        # Existing WOs keep their stored value
+        print(f'existing bake WO {bake_wo.id}: x_fc_bake_temp_uom = {bake_wo.x_fc_bake_temp_uom}')
+
+    # New WO should default from current company setting
+    new_wo_vals = {
+        'production_id': mo.id, 'name': 'Test Bake WO',
+        'workcenter_id': mo.workorder_ids[0].workcenter_id.id,
+    }
+    new_wo = env['mrp.workorder'].sudo().create(new_wo_vals)
+    print(f'NEW WO {new_wo.id}: x_fc_bake_temp_uom = {new_wo.x_fc_bake_temp_uom}  (should be C)')
+    new_wo.sudo().unlink()
+
+# Restore F default
+co.sudo().x_fc_default_temp_uom = 'F'
+print('Restored to °F.')
+env.cr.commit()