feat(plating): wire deferred UoM defaults — bake oven, bake window, coating, tank

Follow-up to the company-level UoM defaults commit. Wires four more
unit-bearing fields to inherit from res.company defaults at create-time.

**1. fp.bake.oven**
  • New `target_temp_uom` (°F / °C) — defaults from
    company.x_fc_default_temp_uom.
  • View: target_temp_min / max now render with a unit picker on the
    same row instead of unitless floats. Rule of thumb: "350–380 °F".

**2. fp.bake.window**
  • New `bake_temp_uom` — defaults from company.x_fc_default_temp_uom.
  • View: replaced hardcoded `°F` span with a live unit picker so the
    label matches whatever unit was actually recorded.

**3. fp.coating.config**
  • New `bake_temperature_uom` — defaults from company.
  • Removed hardcoded "Bake Temperature (°F)" label; the field is
    now unit-agnostic and the unit travels with the value.

**4. fp.tank.volume_uom**
  • Default now derives from company.x_fc_default_volume_uom via a
    small mapping (gal → gal_us, L → l, imp_gal → gal_imp). The
    selection itself stays the same — tanks already supported all
    common volume units; we just pre-pick the right one per company.

**Verified end-to-end** (scripts/fp_uom_smoke2.py):
  • Switching company default to °C + Litres
  • New oven gets C ✓
  • New bake window gets C ✓
  • New coating config gets C ✓
  • New tank gets `l` ✓ (mapped from company `L`)
  • Restored defaults afterwards

Existing records keep their stored uom — no surprise mutation.

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

fusion_plating/fusion_plating_configurator/__manifest__.py

@@ -5,7 +5,7 @@
 
 {
     'name': 'Fusion Plating — Configurator',
-    'version': '19.0.5.1.0',
+    'version': '19.0.5.2.0',
     'category': 'Manufacturing/Plating',
     'summary': 'Quotation configurator with part catalog, coating configs, and formula-based pricing engine.',
     'description': """

fusion_plating/fusion_plating_configurator/models/fp_coating_config.py

@@ -64,8 +64,14 @@ class FpCoatingConfig(models.Model):
         help='Maximum time between plate exit and bake start. Typically 4h per AMS 2759/9.',
     )
     bake_temperature = fields.Float(
-        string='Bake Temperature (°F)', default=375.0,
-        help='Relief bake temperature. Typical: 375°F for steel ≥ HRC 40.',
+        string='Bake Temperature', default=375.0,
+        help='Relief bake temperature. Default 375 (°F per AMS 2759/9 for '
+             'steel ≥ HRC 40). Unit follows bake_temperature_uom.',
+    )
+    bake_temperature_uom = fields.Selection(
+        [('F', '°F'), ('C', '°C')],
+        string='Temp Unit',
+        default=lambda self: self.env.company.x_fc_default_temp_uom or 'F',
     )
     bake_duration_hours = fields.Float(
         string='Bake Duration (hours)', default=23.0,