fix(api): mark StatsDTO totalPersons + totalDocuments as required

Mirrors what npm run generate:api would emit against the StatsDTO
record (all three @Schema(REQUIRED) annotations). Round-1 fix only
updated totalStories; this brings the other two into line.

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

frontend/src/lib/generated/api.ts

@@ -2138,9 +2138,9 @@ export interface components {
         };
         StatsDTO: {
             /** Format: int64 */
-            totalPersons?: number;
+            totalPersons: number;
             /** Format: int64 */
-            totalDocuments?: number;
+            totalDocuments: number;
             /** Format: int64 */
             totalStories: number;
         };