Add source bundle validation and inspection

internal/app/inspect_test.go

@@ -0,0 +1,40 @@
+package app
+
+import (
+	"bytes"
+	"context"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+func TestInspectPrintsBundleSummary(t *testing.T) {
+	var stdout bytes.Buffer
+	err := Inspect(context.Background(), InspectOptions{
+		Path:   filepath.Join("..", "bundle", "testdata", "valid_bundle"),
+		Stdout: &stdout,
+	})
+	if err != nil {
+		t.Fatalf("Inspect() error = %v", err)
+	}
+	output := stdout.String()
+	for _, want := range []string{
+		"Bundles: 1",
+		"path=.",
+		"id=weather.daily.brentwood.2026-05-30",
+		"created=2026-05-30T11:10:00Z",
+		"report.md size=16",
+		"summary.txt size=8",
+	} {
+		if !strings.Contains(output, want) {
+			t.Fatalf("Inspect() output = %q, want substring %q", output, want)
+		}
+	}
+}
+
+func TestInspectRequiresPath(t *testing.T) {
+	err := Inspect(context.Background(), InspectOptions{})
+	if err == nil || !strings.Contains(err.Error(), "requires a path") {
+		t.Fatalf("Inspect() error = %v, want required path", err)
+	}
+}