fix(chat): drop thin semantic_shadow stub after agent PU6 merge

Keep applySemanticShadow path from feature/pu6-semantic-summary.

Co-authored-by: Cursor <cursoragent@cursor.com>

internal/ctxmgr/semantic_shadow.go

@@ -1,48 +0,0 @@
-package ctxmgr
-
-import (
-	"context"
-	"os"
-	"strings"
-)
-
-// SemanticSummaryShadowEnabled reports SEMANTIC_SUMMARY_SHADOW (default off).
-func SemanticSummaryShadowEnabled() bool {
-	v := strings.TrimSpace(os.Getenv("SEMANTIC_SUMMARY_SHADOW"))
-	return v == "1" || strings.EqualFold(v, "true") || strings.EqualFold(v, "yes")
-}
-
-// MaybeApplySemanticShadow optionally annotates a deterministic summary when the
-// shadow flag is on. It never drops Facts; on "model" failure it keeps the
-// deterministic narrative and marks freshness. Summarizer has no tool rights.
-func MaybeApplySemanticShadow(ctx context.Context, sum *ChatSummary, authorizedOnly bool) *ChatSummary {
-	_ = ctx
-	if sum == nil || !SemanticSummaryShadowEnabled() {
-		return sum
-	}
-	if !authorizedOnly {
-		// Refuse to summarize unauthorized views.
-		out := *sum
-		if out.Facts == nil {
-			out.Facts = map[string]string{}
-		}
-		out.Facts["semantic_shadow"] = "skipped_unauthorized_view"
-		return &out
-	}
-	out := *sum
-	if out.Facts == nil {
-		out.Facts = map[string]string{}
-	}
-	// Deterministic shadow stub (no external LLM in unit path). Real PI can
-	// replace Narrative later behind the same flag; failure keeps deterministic.
-	shadow := strings.TrimSpace(out.Narrative)
-	if shadow == "" {
-		shadow = "（语义摘要影子：无叙事，保留事实槽位）"
-	} else if !strings.Contains(shadow, "[shadow]") {
-		shadow = "[shadow] " + shadow
-	}
-	out.Narrative = shadow
-	out.Facts["semantic_shadow"] = "applied"
-	out.Facts["semantic_shadow_freshness"] = "deterministic_fallback_ok"
-	return &out
-}

internal/ctxmgr/semantic_shadow_test.go

@@ -1,40 +0,0 @@
-package ctxmgr
-
-import "testing"
-
-func TestSemanticSummaryShadowDefaultOff(t *testing.T) {
-	t.Setenv("SEMANTIC_SUMMARY_SHADOW", "")
-	if SemanticSummaryShadowEnabled() {
-		t.Fatal("default off")
-	}
-	in := &ChatSummary{SessionID: "s1", Narrative: "hello", Facts: map[string]string{"a": "1"}}
-	out := MaybeApplySemanticShadow(t.Context(), in, true)
-	if out.Narrative != "hello" || out.Facts["semantic_shadow"] != "" {
-		t.Fatalf("unchanged when off: %+v", out)
-	}
-}
-
-func TestSemanticSummaryShadowAuthorized(t *testing.T) {
-	t.Setenv("SEMANTIC_SUMMARY_SHADOW", "1")
-	in := &ChatSummary{SessionID: "s1", Narrative: "topic", Facts: map[string]string{"k": "v"}}
-	out := MaybeApplySemanticShadow(t.Context(), in, true)
-	if !stringsHasPrefix(out.Narrative, "[shadow]") {
-		t.Fatalf("narrative=%q", out.Narrative)
-	}
-	if out.Facts["k"] != "v" || out.Facts["semantic_shadow"] != "applied" {
-		t.Fatalf("facts=%v", out.Facts)
-	}
-}
-
-func TestSemanticSummaryShadowUnauthorizedSkipped(t *testing.T) {
-	t.Setenv("SEMANTIC_SUMMARY_SHADOW", "true")
-	in := &ChatSummary{SessionID: "s1", Narrative: "x", Facts: map[string]string{}}
-	out := MaybeApplySemanticShadow(t.Context(), in, false)
-	if out.Facts["semantic_shadow"] != "skipped_unauthorized_view" {
-		t.Fatalf("%v", out.Facts)
-	}
-}
-
-func stringsHasPrefix(s, p string) bool {
-	return len(s) >= len(p) && s[:len(p)] == p
-}

internal/ctxmgr/summarizer.go

@@ -199,7 +199,6 @@ func (m *ContextManager) GenerateRollingSummary(ctx context.Context, sessionID s
 
 	// 保存并返回
 	_ = m.SaveChatSummary(ctx, newSum)
-	newSum = MaybeApplySemanticShadow(ctx, newSum, true)
 	return newSum, nil
 }