chore: import clean Agent Desk snapshot (2/7)

internal/ai/tooling/reply_safety.go

@@ -0,0 +1,41 @@
+package tooling
+
+import (
+	"fmt"
+	"strings"
+	"unicode"
+)
+
+const maxCustomerReplyRunes = 8000
+
+// NormalizeCustomerReply applies the final plain-text boundary before an AI
+// response enters a customer conversation. It rejects likely credential
+// assignments instead of masking them, because a masked secret is not useful
+// customer-facing content.
+func NormalizeCustomerReply(value string) (string, error) {
+	value = strings.TrimSpace(value)
+	if value == "" {
+		return "", fmt.Errorf("ai reply is empty")
+	}
+	if secretAssignmentPattern.MatchString(value) {
+		return "", fmt.Errorf("ai reply contains sensitive credential data")
+	}
+	var builder strings.Builder
+	for _, r := range value {
+		if unicode.IsControl(r) && r != '\n' && r != '\t' {
+			continue
+		}
+		builder.WriteRune(r)
+	}
+	value = strings.TrimSpace(builder.String())
+	for strings.Contains(value, "\n\n\n") {
+		value = strings.ReplaceAll(value, "\n\n\n", "\n\n")
+	}
+	if value == "" {
+		return "", fmt.Errorf("ai reply is empty")
+	}
+	if len([]rune(value)) > maxCustomerReplyRunes {
+		return "", fmt.Errorf("ai reply exceeds maximum length")
+	}
+	return value, nil
+}