fix: Report the real reason verify falls back to archive-only checks

resolveGlobals can fail for two distinct reasons — no MongoDB URI, or no
resolvable database name — and verify.go was printing a hardcoded
no-URI note regardless of which one occurred, misleading an operator
whose URI was fine but whose database name could not be resolved.

vantagectl/internal/cmd/verify.go

@@ -33,9 +33,9 @@ func newVerifyCmd() *cobra.Command {
 
 			opt := backup.VerifyOptions{Archive: archive}
 
-			// A database is optional here. resolveGlobals fails without a URI,
-			// so its error is a signal to verify the archive alone rather than
-			// a reason to stop.
+			// A database is optional here. resolveGlobals fails without a URI or
+			// without a resolvable database name, and either error is a signal to
+			// verify the archive alone rather than a reason to stop.
 			var client *mongo.Client
 			if g, gerr := resolveGlobals(c); gerr == nil {
 				client, err = connect(ctx, g)
@@ -47,8 +47,8 @@ func newVerifyCmd() *cobra.Command {
 				opt.Database = g.Database
 				opt.KeyHex = g.KeyHex
 			} else {
-				fmt.Fprintln(c.ErrOrStderr(),
-					"note: no MongoDB URI, so this checks the archive and the key only")
+				fmt.Fprintf(c.ErrOrStderr(),
+					"note: %v, so this checks the archive and the key only\n", gerr)
 			}
 
 			rep, err := backup.Verify(ctx, opt)