merge: integrate final-artifact-vault into local_dev (authorized exception)

User authorized lifting CURRENT FAV whole-branch merge protection on
2026-09-23. Keep FAV_DEGRADED_READ/FAV_PUBLISHER_ENABLED default false.
Drop duplicate goose 00034 (local_dev already has 00036). Preserve
agentx workspace admin routes and pin-export wiring.

internal/ctxmgr/chat_turns.go

@@ -164,7 +164,6 @@ func (m *ContextManager) acquireChatTurnDB(
 	return &AcquireTurnResult{Record: rec, WonLease: true}, nil
 }
 
-
 const maxMemTurns = 2000
 const memTurnTTL = 2 * time.Hour
 
@@ -352,3 +351,49 @@ func (m *ContextManager) GetChatTurn(ctx context.Context, sessionID, clientTurnI
 	cp := *rec
 	return &cp, nil
 }
+
+// GetChatTurnByAssistantMessageID 按会话 + 助手消息定位回合；用于 copy_only 显式 pin。
+func (m *ContextManager) GetChatTurnByAssistantMessageID(ctx context.Context, sessionID string, assistantMessageID int64) (*ChatTurnRecord, error) {
+	if sessionID == "" || assistantMessageID <= 0 {
+		return nil, ErrChatTurnNotFound
+	}
+	if m.pool != nil {
+		var rec ChatTurnRecord
+		var completedAt *time.Time
+		var leaseExpiresAt *time.Time
+		err := m.pool.QueryRow(ctx, `
+			SELECT id, session_id, client_turn_id,
+			       COALESCE(user_id, 0), COALESCE(project_id, 0),
+			       COALESCE(user_message_id, 0), COALESCE(assistant_message_id, 0),
+			       request_body_sha256, status,
+			       COALESCE(first_request_id, ''), COALESCE(last_request_id, ''),
+			       attempt_count, created_at, updated_at, completed_at, lease_expires_at
+			FROM chat_turns
+			WHERE session_id = $1 AND assistant_message_id = $2
+			ORDER BY id DESC
+			LIMIT 1
+		`, sessionID, assistantMessageID).Scan(
+			&rec.ID, &rec.SessionID, &rec.ClientTurnID,
+			&rec.UserID, &rec.ProjectID,
+			&rec.UserMessageID, &rec.AssistantMessageID,
+			&rec.RequestBodySHA256, &rec.Status,
+			&rec.FirstRequestID, &rec.LastRequestID,
+			&rec.AttemptCount, &rec.CreatedAt, &rec.UpdatedAt, &completedAt, &leaseExpiresAt,
+		)
+		if err != nil {
+			return nil, ErrChatTurnNotFound
+		}
+		rec.CompletedAt = completedAt
+		rec.LeaseExpiresAt = leaseExpiresAt
+		return &rec, nil
+	}
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	for _, rec := range m.turns {
+		if rec != nil && rec.SessionID == sessionID && rec.AssistantMessageID == assistantMessageID {
+			cp := *rec
+			return &cp, nil
+		}
+	}
+	return nil, ErrChatTurnNotFound
+}

internal/ctxmgr/finalize_export_test.go

@@ -0,0 +1,46 @@
+package ctxmgr
+
+import (
+	"context"
+	"testing"
+
+	"chat-agent-system/internal/replyexport"
+)
+
+func TestFinalizeAssistantTaskMessageRecalculatesExportColumns(t *testing.T) {
+	m := NewContextManager(nil, nil, TimeDecayConfig{})
+	ctx := context.Background()
+	id, err := m.RecordUserMessageWithID(ctx, "sess-fav", 1, "assistant", "占位", "", "", map[string]any{"task_status": "pending"})
+	if err != nil || id <= 0 {
+		t.Fatalf("record: %v %d", err, id)
+	}
+	body := "# 完整助手终态正文\n\n这是一段足够长的结构化说明，用于重算 export_policy。"
+	if err := m.FinalizeAssistantTaskMessage(ctx, id, body, map[string]any{}, "completed"); err != nil {
+		t.Fatal(err)
+	}
+	msg, err := m.GetMessageByID(ctx, id)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if msg.ExportPolicy != string(replyexport.PolicyFull) {
+		t.Fatalf("export_policy=%q", msg.ExportPolicy)
+	}
+	if msg.ContentSha256 == "" || msg.Content != body {
+		t.Fatalf("sha/body missing: %+v", msg)
+	}
+}
+
+func TestCompleteChatTurnAfterFinalize(t *testing.T) {
+	m := NewContextManager(nil, nil, TimeDecayConfig{})
+	ctx := context.Background()
+	if _, err := m.AcquireChatTurn(ctx, "sess-fav", "turn-1", "abc", "req-1", 1, 9); err != nil {
+		t.Fatal(err)
+	}
+	if err := m.CompleteChatTurn(ctx, "sess-fav", "turn-1", 42); err != nil {
+		t.Fatal(err)
+	}
+	rec, err := m.GetChatTurn(ctx, "sess-fav", "turn-1")
+	if err != nil || rec.Status != TurnStatusCompleted || rec.AssistantMessageID != 42 || rec.CompletedAt == nil {
+		t.Fatalf("turn not completed: %+v %v", rec, err)
+	}
+}

internal/ctxmgr/message_update.go

@@ -7,6 +7,7 @@ import (
 	"fmt"
 
 	"chat-agent-system/internal/app/uow"
+	"chat-agent-system/internal/replyexport"
 
 	"github.com/jackc/pgx/v5/pgconn"
 	"github.com/jackc/pgx/v5/pgxpool"
@@ -68,6 +69,16 @@ func (m *ContextManager) FinalizeAssistantTaskMessage(ctx context.Context, messa
 		meta["task_status"] = taskStatus
 	}
 
+	kind, cap := replyexport.EvaluatePolicy(replyexport.PolicyOptions{
+		Role:    "assistant",
+		Status:  nzStatus(taskStatus),
+		Content: content,
+	})
+	meta["content_kind"] = string(kind)
+	meta["export_policy"] = string(cap.Policy)
+	meta["content_revision"] = cap.ContentRevision
+	meta["content_sha256"] = cap.ContentSha256
+
 	if m.pool != nil || hasUoW(ctx) {
 		metaJSON, err := json.Marshal(meta)
 		if err != nil {
@@ -76,9 +87,12 @@ func (m *ContextManager) FinalizeAssistantTaskMessage(ctx context.Context, messa
 		tag, err := execChat(ctx, m.pool, `
 			UPDATE chat_messages
 			SET content = $1,
-			    metadata = COALESCE(metadata, '{}'::jsonb) || $2::jsonb
-			WHERE id = $3
-		`, content, metaJSON, messageID)
+			    metadata = COALESCE(metadata, '{}'::jsonb) || $2::jsonb,
+			    export_policy = $3,
+			    content_sha256 = $4,
+			    content_kind = $5
+			WHERE id = $6
+		`, content, metaJSON, string(cap.Policy), cap.ContentSha256, string(kind), messageID)
 		if err != nil {
 			return fmt.Errorf("finalize assistant task message failed: %w", err)
 		}
@@ -100,6 +114,10 @@ func (m *ContextManager) FinalizeAssistantTaskMessage(ctx context.Context, messa
 				for k, v := range meta {
 					msgs[i].Metadata[k] = v
 				}
+				msgs[i].ExportPolicy = string(cap.Policy)
+				msgs[i].ContentSha256 = cap.ContentSha256
+				msgs[i].ContentKind = string(kind)
+				msgs[i].ContentRevision = cap.ContentRevision
 				m.messages[sid][i] = msgs[i]
 				return nil
 			}
@@ -168,3 +186,10 @@ func execChat(ctx context.Context, pool *pgxpool.Pool, q string, args ...any) (p
 	}
 	return pool.Exec(ctx, q, args...)
 }
+
+func nzStatus(taskStatus string) string {
+	if taskStatus == "" {
+		return "completed"
+	}
+	return taskStatus
+}