fix: resolve QG-001 typography token drift and QG-006 style violations

Replace raw line-height values with --leading-none/--leading-loose
design tokens in 3 CSS files. Fix 7 PHP style issues: import ordering,
unused imports, brace placement, multi-line argument formatting.

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

tests/Unit/Module/LayoutContextProviderTest.php

@@ -77,7 +77,10 @@ final class LayoutContextProviderTest extends TestCase
         // addressbook.nav via the provider loop
         $layoutNav = appBuildLayoutNavContext([], [], []);
 
-        self::assertArrayHasKey('addressbook.nav', $layoutNav,
-            'addressbook.nav key must be present in layoutNav when module is active');
+        self::assertArrayHasKey(
+            'addressbook.nav',
+            $layoutNav,
+            'addressbook.nav key must be present in layoutNav when module is active'
+        );
     }
 }