feat(model): Top5#1 结构化流事件 + WS 事件体系（对齐 OpenClaw AssistantMessageEvent）

- 新增 model/stream.go：StreamKind(text/thinking/tool_call 各 start/delta/end + tool_execution)
  + StreamEvent{Kind,Delta,Index,ID}。
- ChatStream 签名 onChunk func(delta string)→onEvent func(StreamEvent)；loop OnStream 同改；
  streamStep 转发结构化事件。
- openai：text_delta + text_start/text_end（正文三段式）；anthropic：文本块 text_*/tool_call_*
  按块 Index（content_block_stop 分支）真分段；fallback：有事件即交付。
- ws_hub：wsEvent 壳补 turnId/seq；新增 broadcastStream；streamChat 每帧打 turnId+seq；
  stream.go 把事件 publish 到 bus ws.stream。
- ws_bridge：streamEventData 映射 text_*→message.start/delta/end、thinking_*→thinking.*、
  tool_call_*→tool_call.*、tool_execution_update→tool_execution.update，未知回退 stream_chunk。
- 前端 ws.ts：解析 message.start/delta/end、thinking.start/delta/end(pendingThinking)、
  tool_call.start/end→addTool、tool_execution.update；保留旧 stream_chunk/thinking/tool_used 兼容；
  types.ts 补 turnId/seq。Docs/api-client.md 增 §3.1 v0.4。

已知限制（注释/文档标注）：turnId 在 OnStream→bus→relay 路径暂为空（StreamEvent 无 turnId 字段，
bus ws.stream 载荷不带 turn）；OpenAI adapter 未解析 tool_call 段；thinking 段两 adapter 暂不发；
tool_execution.update 是保留项（随工具循环钩子后置）。go build/vet/test + 前端 tsc 全绿。

internal/runtime/loop/loop.go

@@ -20,6 +20,7 @@ import (
 	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/agent"
 	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/guardrail"
 	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/memory"
+	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/model"
 	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/persist"
 	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/tool"
 	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/trace"
@@ -79,7 +80,7 @@ type Loop struct {
 	guards     *guardrail.Pipeline
 	personaID  string
 	maxRounds  int
-	onStream   func(delta string)
+	onStream   func(model.StreamEvent)
 	log        *slog.Logger
 }
 

internal/runtime/loop/loop_test.go

@@ -281,7 +281,7 @@ func TestRun_StreamDeltas(t *testing.T) {
 	var deltas []string
 	l := New(Options{
 		Agent:     a,
-		OnStream:  func(d string) { mu.Lock(); deltas = append(deltas, d); mu.Unlock() },
+		OnStream:  func(ev model.StreamEvent) { mu.Lock(); deltas = append(deltas, ev.Delta); mu.Unlock() },
 		MaxRounds: 8,
 	})
 
@@ -306,7 +306,7 @@ func TestRun_StreamGuardrailBlocks(t *testing.T) {
 	pipe := guardrail.New(guardrail.WithGuard(g))
 	ad := &mockAdapter{}
 	a := newTestAgent(t, ad, nil)
-	l := New(Options{Agent: a, Guards: pipe, OnStream: func(string) {}, MaxRounds: 8})
+	l := New(Options{Agent: a, Guards: pipe, OnStream: func(model.StreamEvent) {}, MaxRounds: 8})
 
 	res, err := l.Run(context.Background(), "sess", []model.Message{model.TextMessage(model.RoleUser, "hi")})
 	if err != nil {

internal/runtime/loop/mocks_test.go

@@ -59,14 +59,14 @@ func (m *mockAdapter) Chat(_ context.Context, req model.Request, _ model.Options
 	return r.resp, r.err
 }
 
-func (m *mockAdapter) ChatStream(_ context.Context, req model.Request, on func(string)) (model.Response, error) {
+func (m *mockAdapter) ChatStream(_ context.Context, req model.Request, on func(model.StreamEvent)) (model.Response, error) {
 	m.streamReqs = append(m.streamReqs, req)
 	i := m.streamCalls
 	m.streamCalls++
 	if i < len(m.chunks) {
 		for _, c := range m.chunks[i] {
 			if on != nil {
-				on(c)
+				on(model.StreamEvent{Kind: model.StreamKindTextDelta, Delta: c})
 			}
 		}
 	}

internal/runtime/loop/options.go

@@ -6,6 +6,7 @@ import (
 	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/agent"
 	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/guardrail"
 	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/memory"
+	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/model"
 	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/persist"
 	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/tool"
 	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/trace"
@@ -47,9 +48,10 @@ type Options struct {
 	// DefaultMaxRounds (8).
 	MaxRounds int
 	// OnStream, when non-nil, switches the loop to the streaming path: the model
-	// adapter's ChatStream is driven directly and each token delta is forwarded
-	// to this callback.
-	OnStream func(delta string)
+	// adapter's ChatStream is driven directly and each structured stream event is
+	// forwarded to this callback (model.StreamEvent), so the frontend can render
+	// body text, tool calls and (eventually) reasoning segments independently.
+	OnStream func(model.StreamEvent)
 	// Log is the base logger. Nil is replaced with a discard logger tagged with
 	// source "runtime/loop".
 	Log *slog.Logger

internal/runtime/loop/stream.go

@@ -31,9 +31,9 @@ func (l *Loop) streamStep(ctx context.Context, messages []model.Message) (*stepO
 		}
 	}
 
-	resp, err := adapter.ChatStream(ctx, req, func(delta string) {
+	resp, err := adapter.ChatStream(ctx, req, func(ev model.StreamEvent) {
 		if l.onStream != nil {
-			l.onStream(delta)
+			l.onStream(ev)
 		}
 	})
 	if err != nil {