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/fusion_plating/views/res_config_settings_views.xml

@@ -37,6 +37,46 @@
                             <field name="x_fc_default_mastery_threshold"/>
                         </setting>
                     </block>
+
+                    <block title="Units of Measure"
+                           name="fp_uom_settings"
+                           help="Default units used wherever the shop records measurements. North-American aerospace shops typically pick °F + mils; metric shops pick °C + microns. Each new record (work order, oven, bath log, thickness reading) inherits these defaults; per-record overrides remain possible.">
+                        <setting id="fp_default_temp_uom"
+                                 string="Temperature"
+                                 help="Bake temps, oven setpoints, bath temperatures.">
+                            <field name="x_fc_default_temp_uom"/>
+                        </setting>
+                        <setting id="fp_default_thickness_uom"
+                                 string="Thickness"
+                                 help="Coating spec targets and Fischerscope readings.">
+                            <field name="x_fc_default_thickness_uom"/>
+                        </setting>
+                        <setting id="fp_default_volume_uom"
+                                 string="Volume"
+                                 help="Bath volumes and chemical addition logs.">
+                            <field name="x_fc_default_volume_uom"/>
+                        </setting>
+                        <setting id="fp_default_mass_uom"
+                                 string="Mass"
+                                 help="Chemical doses, parts weight, waste manifests.">
+                            <field name="x_fc_default_mass_uom"/>
+                        </setting>
+                        <setting id="fp_default_pressure_uom"
+                                 string="Pressure"
+                                 help="Compressed-air pressure, agitation, filtration.">
+                            <field name="x_fc_default_pressure_uom"/>
+                        </setting>
+                        <setting id="fp_default_current_density_uom"
+                                 string="Current Density"
+                                 help="Electrolytic plating bath current density.">
+                            <field name="x_fc_default_current_density_uom"/>
+                        </setting>
+                        <setting id="fp_default_area_uom"
+                                 string="Area"
+                                 help="Part surface area, masking area.">
+                            <field name="x_fc_default_area_uom"/>
+                        </setting>
+                    </block>
                 </app>
             </xpath>
         </field>