fix(configurator): centre Process Editor button icon + make icon white

- Icon + label now share an inline-flex row with align-items: center,
  so both sit on the button's vertical midline regardless of line-
  height inheritance.
- Dedicated gap (10px) replaces the me-2 utility so the _hint block's
  .fa { margin-bottom: 16px } can't bleed in and push the icon off.
- Icon colour forced to #ffffff to match the button's white label —
  contrast against btn-primary green is now clean.

fusion_plating_configurator → 19.0.12.3.0

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': '19.0.12.2.0',
+    'version': '19.0.12.3.0',
     'category': 'Manufacturing/Plating',
     'summary': 'Quotation configurator with part catalog, coating configs, and formula-based pricing engine.',
     'description': """