Add ReasoningEffort 'minimal'

Author: brumhard

src/main/java/io/github/sashirestela/openai/domain/chat/ChatRequest.java

@@ -160,14 +160,17 @@ public static Audio of(Voice voice, AudioFormat format) {
     }
 
     public enum ReasoningEffort {
+        @JsonProperty("minimal")
+        MINIMAL,
+
         @JsonProperty("low")
         LOW,
 
         @JsonProperty("medium")
         MEDIUM,
 
         @JsonProperty("high")
-        HIGH;
+        HIGH
     }
 
     @Getter