fix(fusion_iot): respect company temperature-unit preference in sensor UI

The sensor readings list always showed raw °C regardless of the
Plating Settings Temperature Unit preference (res.company.x_fc_default_temp_uom).
On a Fahrenheit-preferred shop, a 40°C reading should render as 105°F.

Fix: add display-aware computed fields alongside the canonical ones.

**fp.tank.reading**
- `value` / `unit` renamed with "(raw)" labels — these are the stored
  canonical values (always °C for temperature, because every
  temperature chip reports in Celsius natively)
- `display_value` + `display_unit` computed from company pref — only
  flips C→F when parameter_type='temperature' AND company pref='F';
  pH/conductivity/etc pass through untouched
- `display_name` now uses display_value so it reads naturally
  ("Sensor — 105.58 °F @ ...") regardless of region

**fp.tank.sensor**
- Mirrored the same pattern on the cached last-reading fields
- `last_reading_display` + `last_reading_display_unit` for lists
- `last_reading_value` hidden behind group_no_one (debug-only)

**Views**
- fp.tank.reading list: show display_value/display_unit, raw value
  hidden by default (toggle from column picker if needed)
- fp.tank.sensor list + form + tank inline: same pattern
- Raw value kept visible as an optional column so data engineers
  can still audit canonical storage

Why store canonical: spec thresholds (alert_min/max) live on the
sensor in °C. If the same Odoo serves a multi-region company
(Canada in C, US affiliate in F), switching a single preference
flips every UI without touching data. Alert logic keeps comparing
canonical values, so out-of-spec holds fire correctly regardless
of display unit.

Verified: 40.88°C raw → 105.58°F display on the live pilot probe
with company pref='F'. All 5 recent readings tested, display
fields updated correctly on every poll.

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

fusion_iot/fusion_plating_iot/__manifest__.py

@@ -5,7 +5,7 @@
 
 {
     'name': 'Fusion Plating — IoT Integration',
-    'version': '19.0.0.1.0',
+    'version': '19.0.0.2.0',
     'category': 'Manufacturing/Plating',
     'summary': 'Wire physical tank sensors to Fusion Plating — live '
                'temperature / chemistry readings with auto quality holds '