Add jep511 module: module import declarations on JDK 25 and 27

Runnable sources, deliberate compile failures, three small modules and nine captured transcripts for import module (JEP 511).

Co-Authored-By: Claude Sonnet 5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01TF9JWFvJSNm6HVzswzZU5a

jep511/src/UnusedAmbiguity.java

@@ -0,0 +1,9 @@
+import module java.base;
+import module java.sql;
+
+public class UnusedAmbiguity {
+    public static void main(String[] args) {
+        // Date is ambiguous between the two modules, but it is never used here, so this compiles.
+        System.out.println("no Date mentioned, no error");
+    }
+}