chore: disable blank issues; link to discussions

Author: woutervroege

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,6 @@
+blank_issues_enabled: false
+
+contact_links:
+  - name: Share an idea or suggest an enhancement
+    url: https://github.com/TypeCellOS/BlockNote/discussions/categories/ideas-enhancements
+    about: Share feature ideas, enhancement suggestions, or other ideas for the BlockNote project.