Add transcript description prompt context

internal/framework/promptcontext/transcript_description.go

@@ -0,0 +1,21 @@
+package promptcontext
+
+import (
+	"fmt"
+	"strings"
+)
+
+// TranscriptDescriptionBlock returns standardized background-only context
+// guidance for prompt builders when a user-supplied description is present.
+func TranscriptDescriptionBlock(transcriptDescription string) string {
+	description := strings.TrimSpace(transcriptDescription)
+	if description == "" {
+		return ""
+	}
+
+	return "Transcript description (background context only):\n" +
+		fmt.Sprintf("%s\n\n", description) +
+		"Use this description only as optional background to interpret ambiguous terms. " +
+		"It must not override the transcript content. " +
+		"Do not invent corrections, facts, names, events, motivations, or speaker intent based on this description.\n\n"
+}