feat(sdk): 插件 SDK（Tool/Skill/Channel 接口 + 注册辅助 + 配置 hook）

pkg/plugins/sdk/tool.go

@@ -0,0 +1,23 @@
+package sdk
+
+import "context"
+
+// Tool is a callable function plus its input JSON Schema. Agents invoke tools
+// directly by name; the dispatcher decodes the agent-provided arguments into
+// args before calling Execute.
+//
+// Implementations must be safe for concurrent use, because Tool dispatch in the
+// runtime may invoke them from multiple goroutines.
+type Tool interface {
+	// Name returns the unique tool identifier the agent uses to invoke it.
+	Name() string
+	// Description explains what the tool does; the model uses it to select a
+	// tool for a task.
+	Description() string
+	// Parameters returns the tool input JSON Schema as a JSON object, for
+	// example {"type":"object","properties":{...}}. A nil map with a nil error
+	// means the tool accepts no arguments.
+	Parameters() (map[string]any, error)
+	// Execute runs the tool with args decoded from the caller's JSON input.
+	Execute(ctx context.Context, args any) (any, error)
+}