支持工具调用：三个AI角色配置、工具注册表与流式工具轮

internal/tools/random_tool.go

@@ -0,0 +1,42 @@
+package tools
+
+import (
+	"encoding/json"
+	"fmt"
+	"math/rand/v2"
+)
+
+type RandomTool struct{}
+
+func (RandomTool) Name() string { return "random_number" }
+func (RandomTool) Description() string {
+	return "生成指定范围内的随机整数，默认 0 到 100（含端点）"
+}
+func (RandomTool) Parameters() map[string]any {
+	return map[string]any{
+		"type": "object",
+		"properties": map[string]any{
+			"min": map[string]any{"type": "integer", "description": "最小值，默认 0"},
+			"max": map[string]any{"type": "integer", "description": "最大值，默认 100"},
+		},
+	}
+}
+
+func (RandomTool) Execute(args json.RawMessage) (string, error) {
+	var p struct {
+		Min *int `json:"min"`
+		Max *int `json:"max"`
+	}
+	_ = json.Unmarshal(args, &p)
+	min, max := 0, 100
+	if p.Min != nil {
+		min = *p.Min
+	}
+	if p.Max != nil {
+		max = *p.Max
+	}
+	if max < min {
+		return "", fmt.Errorf("max (%d) 不能小于 min (%d)", max, min)
+	}
+	return fmt.Sprintf("%d", rand.IntN(max-min+1)+min), nil
+}