feat: Enhance chat completion with tool calling capabilities

- Added support for tools in ChatCompletionRequest, including tool choice and parallel tool calls.
- Introduced ChatCompletionTool and ChatCompletionFunction classes to define tool specifications.
- Updated ChatMessage to include tool calls and tool call IDs.
- Created ChatToolCall and ChatToolFunction classes for managing tool call details.
- Modified TextCompletionClient to support tool calling.
- Updated Grader and Grader2 classes to handle new tool-related logic.
- Enhanced Agent and AgentTest classes to incorporate tool calling in agent workflows.
- Added tests for tool calling functionality in CachedClientTest and CompletionClientTest.

src/main/java/de/extio/lmlib/grader/Grader.java

@@ -36,6 +36,7 @@ public class Grader {
 								Only provide the response as a single word and no preamble and no explanation.""",
 						"Here is the text:\n" + text + "\n\n" +
 						"Here is the user question: " + question),
+					null,
 					true);
 			LOGGER.info(completion.response());
 			score += Boolean.parseBoolean(completion.response().strip()) ? 1 : -1;

src/main/java/de/extio/lmlib/grader/Grader2.java

@@ -50,6 +50,7 @@ public class Grader2 {
 					- 'false': The text does not provide a truthful answer.
 					Only provide the response as a single word. Do not include any preamble or explanation.
 					""".formatted(question, text)),
+					null,
 					true);
 			LOGGER.info(completion.response());
 			score += Boolean.parseBoolean(completion.response().strip()) ? 1 : -1;

src/main/java/de/extio/lmlib/grader/agent/AnswerGrader.java

@@ -30,6 +30,7 @@ public class AnswerGrader {
 						The question is: {{questions}}
 						The answer is: {{answer}}
 						""",
+				null,
 				new JsonAgentResponseHandler(),
 				context -> {
 					context.setSkipCache(true);

src/main/java/de/extio/lmlib/grader/agent/AnswerGrader2.java

@@ -42,6 +42,7 @@ public class AnswerGrader2 {
 						### Output Format
 						{{qaOutputFormat}}
 						""",
+						null,
 				new JsonAgentResponseHandler(),
 				context -> {
 					final Boolean outputDescription = context.getValue("qaOutputDescription", Boolean.class);

src/main/java/de/extio/lmlib/grader/agent/AnswerGraderBinary.java

@@ -33,6 +33,7 @@ public class AnswerGraderBinary {
 				Output Format:
 				{{qaOutputFormat}}
 				""",
+				null,
 				new JsonAgentResponseHandler(),
 				context -> {
 					final Boolean outputDescription = context.getValue("qaOutputDescription", Boolean.class);