Update usage from aiClient to chatClient in docs (#281)

Author: Yeonwoo Kim

spring-ai-docs/src/main/antora/modules/ROOT/pages/api/clients/azure-openai.adoc

@@ -63,7 +63,7 @@ public class ChatController {
 
     @GetMapping("/ai/generate")
     public Map generate(@RequestParam(value = "message", defaultValue = "Tell me a joke") String message) {
-        return Map.of("generation", chatClient.generate(message));
+        return Map.of("generation", chatClient.call(message));
     }
 }
 ----

spring-ai-docs/src/main/antora/modules/ROOT/pages/api/output-parser.adoc

@@ -106,9 +106,9 @@ Here is a controller class that shows these classes in use
 
         PromptTemplate promptTemplate = new PromptTemplate(userMessage, Map.of("actor", actor, "format", outputParser.getFormat() ));
         Prompt prompt = promptTemplate.create();
-        Generation generation = aiClient.generate(prompt).getGeneration();
+        Generation generation = chatClient.call(prompt).getResult();
 
-        ActorsFilms actorsFilms = outputParser.parse(generation.getText());
+        ActorsFilms actorsFilms = outputParser.parse(generation.getOutput().getContent());
         return actorsFilms;
     }
 ```

spring-ai-docs/src/main/antora/modules/ROOT/pages/api/prompt.adoc

@@ -200,7 +200,7 @@ PromptTemplate promptTemplate = new PromptTemplate("Tell me a {adjective} joke a
 
 Prompt prompt = promptTemplate.create(Map.of("adjective", adjective, "topic", topic));
 
-return aiClient.generate(prompt).getGeneration();
+return chatClient.call(prompt).getResult();
 ```
 
 Another example taken from the https://github.com/Azure-Samples/spring-ai-azure-workshop/blob/main/3-README-prompt-roles.md[AI Workshop on Roles] is shown below.
@@ -224,7 +224,7 @@ Message systemMessage = systemPromptTemplate.createMessage(Map.of("name", name,
 
 Prompt prompt = new Prompt(List.of(userMessage, systemMessage));
 
-List<Generation> response = aiClient.generate(prompt).getGenerations();
+List<Generation> response = chatClient.call(prompt).getResults();
 
 ```