docs(theme): clarify tooltip on schema expansion control

Switch the aria-label / title from "Schema expansion depth" to a more
descriptive "Set how deep schemas auto-expand" so hovering the icon
explains what the control does.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Author: sserrata

packages/docusaurus-theme-openapi-docs/src/theme/SchemaExpansion/index.tsx

@@ -110,8 +110,8 @@ const SchemaExpansionControl: React.FC = () => {
   const levels = Array.from({ length: config.max + 1 }, (_, i) => i);
   const buttonLabel = translate({
     id: "theme.openapi.schema.expansion.button",
-    message: "Schema expansion depth",
-    description: "Aria/title for the schema expansion icon button",
+    message: "Set how deep schemas auto-expand",
+    description: "Aria/title tooltip for the schema expansion icon button",
   });
   const allLabel = translate({
     id: "theme.openapi.schema.expansion.all",