fix: thorough dark mode fixes across all OWL templates and CSS

- Replace Bootstrap badge classes with theme-aware woo-badge classes in
  product mapping tabs
- Replace <code> with theme-aware .woo-code class
- Replace all text-muted with woo-text-muted using CSS custom properties
- Add client action wrapper background
- Add theme-aware select/checkbox/strong/input overrides
- Add .woo-code, .woo-text-muted, .woo-text-faint utility classes

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

fusion-woo-odoo/fusion_woocommerce/static/src/xml/dashboard.xml

@@ -125,7 +125,7 @@
                                                 <t t-esc="inst.last_sync"/>
                                             </t>
                                             <t t-else="">
-                                                <span class="text-muted">Never</span>
+                                                <span class="woo-text-muted">Never</span>
                                             </t>
                                         </td>
                                     </tr>