Add issue template chooser config

Disable blank issues and add Discussions as a contact link.

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

Author: brunoborges

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,5 @@
+blank_issues_enabled: false
+contact_links:
+  - name: 💬 Discussions
+    url: https://github.com/javaevolved/javaevolved.github.io/discussions
+    about: Ask questions, share ideas, or discuss patterns.