Update model-integration abi spec for generated LlmClientConfig accessors

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Author: abhishekkrthakur

model-integration/abi-spec.json

@@ -36,6 +36,7 @@
       "public ai.vespa.llm.clients.LlmClientConfig$Builder model(java.lang.String)",
       "public ai.vespa.llm.clients.LlmClientConfig$Builder temperature(double)",
       "public ai.vespa.llm.clients.LlmClientConfig$Builder maxTokens(int)",
+      "public ai.vespa.llm.clients.LlmClientConfig$Builder reasoningEffort(java.lang.String)",
       "public final boolean dispatchGetConfig(com.yahoo.config.ConfigInstance$Producer)",
       "public final java.lang.String getDefMd5()",
       "public final java.lang.String getDefName()",
@@ -78,7 +79,8 @@
       "public java.lang.String endpoint()",
       "public java.lang.String model()",
       "public double temperature()",
-      "public int maxTokens()"
+      "public int maxTokens()",
+      "public java.lang.String reasoningEffort()"
     ],
     "fields" : [
       "public static final java.lang.String CONFIG_DEF_MD5",