chore: ratatui 0.30 maintenance + collaboration baseline (#1)

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,5 @@
+blank_issues_enabled: false
+contact_links:
+  - name: Security report
+    url: https://github.com/srothgan/tui-textarea/security/advisories/new
+    about: Please report security vulnerabilities privately.