fix(ai-tools): update maxLength in OpenAPI spec to 50000

Align with the agreed limit of ~100K tokens (50K chars for Japanese).

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

apps/app/src/features/ai-tools/suggest-path/server/routes/apiv3/index.ts

@@ -111,7 +111,7 @@ const validator = [
  *               body:
  *                 type: string
  *                 description: The page content to analyze for path suggestions
- *                 maxLength: 100000
+ *                 maxLength: 50000
  *     responses:
  *       200:
  *         description: Path suggestions generated successfully