Fix smoke test: stay on the EdtfTemporal interface

The previous Smoke.java called i.upper() on a variable typed as
EdtfTemporal, but upper() is declared on EdtfInterval (the
permitted subtype) — not on the sealed interface. The compiler
rejected this with 'cannot find symbol' against the published
0.2.0 jar, breaking the smoke workflow.

Replace the upper-endpoint inspection with a type() call so the
smoke source stays on the EdtfTemporal-only API surface, which is
stable across all releases since 0.2.0. The build.xml assertion
list adds a corresponding 'interval type: INTERVAL' substring
check so the smoke still verifies the interval parsed correctly.

Co-Authored-By: Claude <noreply@anthropic.com>

Author: jeffreyameyer

smoke/build.xml

@@ -59,6 +59,7 @@
                 <contains string="${smoke.stdout}" substring="canonical: 2020-05-15"/>
                 <contains string="${smoke.stdout}" substring="type: DATE"/>
                 <contains string="${smoke.stdout}" substring="interval canonical: 2020/.."/>
+                <contains string="${smoke.stdout}" substring="interval type: INTERVAL"/>
             </and>
         </condition>
         <fail unless="smoke.passed"

smoke/src/Smoke.java

@@ -23,6 +23,6 @@ public static void main(String[] args) {
         // Cover an interval too.
         EdtfTemporal i = Edtf.parse("2020/..");
         System.out.println("interval canonical: " + i.toEdtfString());
-        System.out.println("interval upper-open: " + i.upper().getClass().getSimpleName());
+        System.out.println("interval type: " + i.type());
     }
 }