Update Java 26 tests with JEP 530 (Primitive Types in Patterns) coverage

Replace generic test files from #3740 with JEP 530-specific test cases:
- Foo.java: primitive type pattern in switch with when guard
- Bar.java: instanceof with primitive type pattern
- Update target platform JRE to JavaSE-26

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: 2 people

org.eclipse.jdt.ls.tests/projects/eclipse/java26/src/main/java/foo/bar/Foo.java

@@ -4,8 +4,12 @@
  * It's a Foo class
  */
 public class Foo {
-	public Foo() {
-		System.out.println();
-		super();
+	// JEP 530: Primitive Types in Patterns, instanceof, and switch (Fourth Preview)
+	static String classify(int value) {
+		return switch (value) {
+			case 0 -> "zero";
+			case int i when i > 0 -> "positive";
+			case int i -> "negative";
+		};
 	}
 }

org.eclipse.jdt.ls.tests/projects/maven/salut-java26/src/main/java/org/sample/Bar.java

@@ -5,10 +5,11 @@
  */
 public class Bar {
 
+    // JEP 530: Primitive Types in Patterns, instanceof, and switch (Fourth Preview)
     public static void main(String[] args) {
-        Object foo = "x";
-        if (foo instanceof String str) {
-            System.out.println(str);
+        Object obj = 42;
+        if (obj instanceof int i) {
+            System.out.println("int value: " + i);
         }
     }
 }