fix(mobile): prevent editor auto-zoom on iOS/Android

Browsers zoom any focused editable element (including contenteditable)
whose font-size is below 16px. Apply font-size: max(1rem, 1em) on
.cm-content inside the mobile media query so the 16px floor is enforced
while still respecting user-set sizes larger than that.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

services/web/frontend/stylesheets/pages/editor/ide-lumiere.scss

@@ -447,5 +447,12 @@ $lum-noise: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' wi
     --font-size-03: 1.125rem;  // 18px (was 16px)
     --toolbar-height: 48px;    // was 40px
     --toolbar-small-height: 40px; // was 32px
+
+    // Prevent iOS/Android auto-zoom when tapping into the editor.
+    // Browsers zoom any focused editable element whose font-size < 16px.
+    // `max(1rem, 1em)` honours the user's size setting if it is already ≥ 16px.
+    .cm-content {
+      font-size: max(1rem, 1em) !important;
+    }
   }
 }