Update LLM integration and add new agent tools and utilities

Refactored LLM handling to use updated langchaingo models and tools, replacing gollm dependencies. Introduced agent-related utilities, tools, and counters for better modular functionality. Added a parser for LLM model configuration and revamped the answering mechanism with enhanced support for tool-based interaction.

pkg/agent/test/main.go

@@ -0,0 +1,34 @@
+package main
+
+import (
+	"reflect"
+
+	"github.com/tmc/langchaingo/llms"
+)
+
+func testFunction(args struct{ a, b int }) {
+	// This is a test function
+}
+
+func main() {
+	v := reflect.New(reflect.TypeOf(testFunction))
+
+	t := reflect.TypeOf(testFunction)
+
+	for i := 0; i < t.NumIn(); i++ {
+		param := t.In(i)
+
+		llms.MessageContent{
+			Role: llms.ChatMessageTypeTool,
+			Parts: []llms.ContentPart{
+				llms.ToolCallResponse{
+					Name: "testFunction",
+				},
+			},
+		}
+		if param.Type().Kind() == reflect.Struct {
+
+		}
+		println(param.Name(), param.Kind().String())
+	}
+}