feat(shm): Cleaner 迁移到 SharedRef(§13.4)

- CleanerInvokeParams/Result 的 Text 改为 TextRef SharedRef
- cleanerProxy: 写 text 到 arena，传 SharedRef，读结果 SharedRef
- 插件侧 cleaner.invoke: 从 SharedRef 读 input，清洗后写回 arena 返回 TextRef
- NewHost(): 分配空间含 arena（256KB）

internal/plugin/proc/corehandler.go

@@ -34,7 +34,7 @@ type coreHandler struct {
 	// invokeTool/invokeCleaner/invokeStageFn/invokeOutput 反向调用插件（内核 → 插件）。
 	// 由 Plugin 注入，注册回调时用它们构造 handler。
 	invokeTool    func(name string, args map[string]interface{}) (interface{}, error)
-	invokeCleaner func(scope, name, text string) (string, error)
+	invokeCleaner func(scope, name string, textRef SharedRef) (SharedRef, error)
 	invokeStageFn func(ctx context.Context, stage string, seq uint64) error
 	invokeOutput  func(channel string, args map[string]interface{}) (interface{}, error)
 
@@ -600,11 +600,16 @@ func (h *coreHandler) cleanerProxy(scope, name string, enabled bool) (func(strin
 		return nil, fmt.Errorf("%s %s 声明 Cleaner，但清洗回调通道未就绪", scope, name)
 	}
 	return func(text string) string {
-		cleaned, err := h.invokeCleaner(scope, name, text)
+		ref, err := h.host.unified.arenaWrite([]byte(text))
 		if err != nil {
 			return text
 		}
-		return cleaned
+		resultRef, err := h.invokeCleaner(scope, name, ref)
+		if err != nil {
+			return text
+		}
+		result := h.host.unified.arenaRead(resultRef)
+		return string(result)
 	}, nil
 }
 

internal/plugin/proc/plugin.go

@@ -222,23 +222,23 @@ func (p *Plugin) invokeTool(name string, args map[string]interface{}) (interface
 }
 
 // invokeCleaner 在插件进程内执行工具或通道注册时提供的 Cleaner 函数。
-func (p *Plugin) invokeCleaner(scope, name, text string) (string, error) {
+func (p *Plugin) invokeCleaner(scope, name string, textRef SharedRef) (SharedRef, error) {
 	if p.proc == nil {
-		return "", ErrProcessExited
+		return SharedRef{}, ErrProcessExited
 	}
 	raw, err := p.proc.Call(MethodCleanerInvoke, CleanerInvokeParams{
-		Scope: scope,
-		Name:  name,
-		Text:  text,
+		Scope:   scope,
+		Name:    name,
+		TextRef: textRef,
 	})
 	if err != nil {
-		return "", err
+		return SharedRef{}, err
 	}
 	var res CleanerInvokeResult
 	if err := json.Unmarshal(raw, &res); err != nil {
-		return "", fmt.Errorf("proc: %s %s Cleaner %s 应答解析失败: %w", p.name, scope, name, err)
+		return SharedRef{}, fmt.Errorf("proc: %s %s Cleaner %s 应答解析失败: %w", p.name, scope, name, err)
 	}
-	return res.Text, nil
+	return res.TextRef, nil
 }
 
 func (p *Plugin) invokeStage(ctx context.Context, stage string, seq uint64) error {

internal/plugin/proc/protocol.go

@@ -213,14 +213,15 @@ type ToolInvokeResult struct {
 
 // CleanerInvokeParams / CleanerInvokeResult：跨进程计算层清洗。
 // Scope 取 tool / input / output，Name 是工具名或通道名。
+// TextRef 指向共享内存 arena 中的实际文本数据。
 type CleanerInvokeParams struct {
-	Scope string `json:"scope"`
-	Name  string `json:"name"`
-	Text  string `json:"text"`
+	Scope   string    `json:"scope"`
+	Name    string    `json:"name"`
+	TextRef SharedRef `json:"text_ref"`
 }
 
 type CleanerInvokeResult struct {
-	Text string `json:"text"`
+	TextRef SharedRef `json:"text_ref"`
 }
 
 const (

internal/plugin/proc/testdata/stageplugin.go

@@ -40,6 +40,9 @@ var (
 
 	shm     []byte
 	shmSize int
+	region  []byte // 完整统一区域 mmap
+	arenaOff uint32
+	arenaUsed uint32
 )
 
 func send(v interface{}) {
@@ -233,6 +236,8 @@ func main() {
 				// 统一区域：前 64B 是 SuperBlock，StageContext 段在其后
 				ctxOff := binary.LittleEndian.Uint32(m[20:])
 				ctxSize := binary.LittleEndian.Uint32(m[24:])
+				region = m
+				arenaOff = binary.LittleEndian.Uint32(m[36:])
 				shm = m[ctxOff : ctxOff+ctxSize]
 			}
 			send(response{ID: req.ID, Result: map[string]interface{}{
@@ -282,9 +287,12 @@ func main() {
 
 		case "cleaner.invoke":
 			var p struct {
-				Scope string `json:"scope"`
-				Name  string `json:"name"`
-				Text  string `json:"text"`
+				Scope   string `json:"scope"`
+				Name    string `json:"name"`
+				TextRef struct {
+					Offset uint32 `json:"offset"`
+					Length uint32 `json:"length"`
+				} `json:"text_ref"`
 			}
 			json.Unmarshal(req.Params, &p)
 			valid := (p.Scope == "tool" && p.Name == "demo_upper") ||
@@ -294,8 +302,22 @@ func main() {
 				send(response{ID: req.ID, Error: "未注册 Cleaner"})
 				continue
 			}
+			// 从 arena 读文本
+			input := string(region[p.TextRef.Offset : p.TextRef.Offset+p.TextRef.Length])
+			output := p.Scope + "-cleaned:" + input
+			// 写回 arena
+			off := arenaUsed
+			if off == 0 {
+				off = 1
+			}
+			end := off + uint32(len(output))
+			copy(region[arenaOff+end-uint32(len(output)):arenaOff+end], output)
+			arenaUsed = end
 			send(response{ID: req.ID, Result: map[string]interface{}{
-				"text": p.Scope + "-cleaned:" + p.Text,
+				"text_ref": map[string]interface{}{
+					"offset": arenaOff + off,
+					"length": uint32(len(output)),
+				},
 			}})
 
 		case "stage.invoke":