Enforce deterministic gateway task policies

Make the server authoritative for thinking, model, search, tools, retry, and output budgets while preserving legacy client behavior.

src/main/kotlin/com/osglab/account/Application.kt

@@ -609,6 +609,7 @@ private fun configuredProviders(config: AppConfig, client: HttpClient): List<Gat
                         endpoint = config.providers.deepSeek.endpoint,
                         apiKey = apiKey,
                         model = config.providers.deepSeek.model,
+                        reasoningModel = config.providers.deepSeek.reasoningModel,
                     ),
                 ),
             )