Initialize narratio Go module and CLI scaffold

internal/adapters/audita/runner.go

@@ -0,0 +1,20 @@
+// Package audita declares the adapter contract for transcript polishing.
+package audita
+
+import "context"
+
+// Runner is a placeholder adapter interface for audita invocation.
+type Runner interface {
+	Run(ctx context.Context, req PolishRequest) (PolishResult, error)
+}
+
+// PolishRequest is a placeholder polish input.
+type PolishRequest struct {
+	MergedTranscriptPath string
+	OutputPath           string
+}
+
+// PolishResult is a placeholder polish output.
+type PolishResult struct {
+	ProcessedPath string
+}