Restore support for Font Awesome Sass config overrides like $fa-font-path

[chalin]

• Since 0.17.0 (Upgrade Font Awesome to 7.3.1, adopt its Sass module API #2750), Font Awesome's Sass loads as a module, which freezes its configuration at the defaults: $fa-* configuration globals set in project Sass compile but no longer have any effect. Under Font Awesome 6 they worked, read at import time. The failure is silent: the build stays green.

• Example: a site that self-hosts the icon webfonts:

  // _variables_project.scss
  $fa-font-path: '../fonts';

  Under 0.16, Font Awesome's generated @font-face rules point at ../fonts/. Under 0.17 they silently revert to the default ../webfonts path: the build stays green and every icon-font request 404s. Same shape for $fa-font-display: swap, which silently reverts to block.

• Documented in the 0.17.0 release report, § Font Awesome 7 (publishes at release). This issue tracks restoring the override hook.

• Exposure: a public-code search finds five sites setting $fa-* configuration in _variables_project.scss, three of them $fa-font-path.

• Proposal: pass site-set values into the module load (@use ... with). Gated on the theme's own Sass module migration: _main.scss still loads Font Awesome via @import, which has no configuration mechanism.