fix: move Swagger UI to /api-docs to allow errorHandler to work correctly

- Changed `app.use(openAPIRouter)` to `app.use("/api-docs", openAPIRouter")`
- Prevents Swagger UI from interfering with unmatched routes and error propagation
- Undefined routes now correctly return "Not Found"
- Global errorHandler middleware now correctly captures all propagated errors

Author: kiwiscode

src/server.ts

@@ -31,7 +31,7 @@ app.use("/health-check", healthCheckRouter);
 app.use("/users", userRouter);
 
 // Swagger UI
-app.use(openAPIRouter);
+app.use("/api-docs", openAPIRouter);
 
 // Error handlers
 app.use(errorHandler());