feat(memory): 记忆 P2（项目索引物化 / decay 回写 / 作用域写规则 / 静默吞点 + loop 级只读红线测试）

plugins/tools/io/knowledge_test.go

@@ -11,6 +11,7 @@ import (
 	"git.yeij.top/AskaEth/Cyrene_v2/internal/db"
 	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/loop"
 	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/memory"
+	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/memory/projectindex"
 	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/tool"
 )
 
@@ -251,6 +252,42 @@ func TestKnowledge_RestrictedEnv_OnlySharedVisible(t *testing.T) {
 	}
 }
 
+// TestKnowledge_SurfacesLinkedProject 钉住审计 2026-10-05 §4：knowledge 工具此前
+// 丢掉了 Result.Project，模型因此够不着「项目索引 → 项目描述」层级。修复后项目
+// 作用域命中必须带出链接的项目条目（id/title/desc），非项目命中则不带该键。
+func TestKnowledge_SurfacesLinkedProject(t *testing.T) {
+	t.Parallel()
+	sr := &stubRetriever{results: []memory.Result{
+		{
+			Item:    memory.MemoryItem{ID: "m1", Content: "项目记忆：Cyrene 用 Go 编写", Kind: memory.KindWorldEvent, Scope: memory.ScopeProject},
+			Score:   0.7,
+			Project: &projectindex.Project{ID: "proj.1", Title: "Cyrene", Desc: "陪伴型 AI 助手"},
+		},
+		{
+			Item:  memory.MemoryItem{ID: "m2", Content: "用户习惯：喜欢冰美式", Kind: memory.KindRelationship, Scope: memory.ScopeUser},
+			Score: 0.4,
+		},
+	}}
+	kt := knowledgeToolForTest(t, WithKnowledgeRetriever(sr))
+
+	ctx := loop.WithSessionEnv(tool.WithTurnPersona(context.Background(), "persona-a"), loop.OwnerEnv())
+	got, err := kt.Execute(ctx, map[string]any{"query": "Cyrene"})
+	if err != nil {
+		t.Fatalf("Execute: %v", err)
+	}
+	results := got.(map[string]any)["results"].([]map[string]any)
+	proj, ok := results[0]["project"].(map[string]any)
+	if !ok {
+		t.Fatalf("项目作用域命中未带出链接项目：%+v", results[0])
+	}
+	if proj["id"] != "proj.1" || proj["title"] != "Cyrene" || proj["desc"] != "陪伴型 AI 助手" {
+		t.Fatalf("project = %+v, want proj.1/Cyrene/陪伴型 AI 助手", proj)
+	}
+	if _, present := results[1]["project"]; present {
+		t.Fatalf("非项目命中不该带 project 键：%+v", results[1])
+	}
+}
+
 // TestKnowledge_OwnerEnv_AllScopes 钉住反向边界：owner（全权限）环境不做隔离过滤，
 // 四类命中都照常返回 —— 修复只收窄群聊/陌生人，绝不误伤主人自己的完整读取。
 func TestKnowledge_OwnerEnv_AllScopes(t *testing.T) {