Dynamically configure cookie and base-url

When `base-url` is the default (i.e. localhost), the cookie is now
configured with the domain doing the request and the webapp is
configured to run requests against the host in the address bar of the
browser.

modules/common/src/main/scala/docspell/common/LenientUri.scala

@@ -83,6 +83,9 @@ case class LenientUri(
       }
     )
 
+  def isLocal: Boolean =
+    host.exists(_.equalsIgnoreCase("localhost"))
+
   def asString: String = {
     val schemePart = scheme.toList.mkString(":")
     val authPart   = authority.map(a => s"//$a").getOrElse("")