chore: firm up bug report (#20724)

.github/ISSUE_TEMPLATE/bug_report.yml

 name: Bug report
-description: Confirmed bugs only. Create a discussion first.
+description: Bug reports require a minimal reproduction and should be preceded by a Discussion first.
 labels: ['type:bug', 'status:requirements', 'priority-5-triage']
 body:
   - type: markdown
     attributes:
       value: |
-        Please don't create these bug reports unless you're an experienced user or absolutely certain you found a bug.
-        It is preferred that you create a [discussion](https://github.com/renovatebot/renovate/discussions/new) first and allow maintainers to decide.
+        Please don't create these bug reports unless you're an experienced user or absolutely certain you found a bug, and you have a [minimal reproduction](https://github.com/renovatebot/renovate/blob/main/docs/development/minimal-reproductions.md).
+        Otherwise, it is preferred that you create a [discussion](https://github.com/renovatebot/renovate/discussions/new) first and allow maintainers to decide.
+        Invalid bug reports can confuse users so will be _deleted_, not closed.
 
   - type: dropdown
     id: how-are-you-running-renovate
@@ -106,8 +107,7 @@ body:
       label: Have you created a minimal reproduction repository?
       description: Please read the [minimal reproductions documentation](https://github.com/renovatebot/renovate/blob/main/docs/development/minimal-reproductions.md) to learn how to make a good minimal reproduction repository.
       options:
-        - 'No reproduction repository'
-        - 'No reproduction, but I have linked to a public repo where it occurs'
-        - 'I have linked to a minimal reproduction repository in the bug description'
+        - 'I have read the minimal reproductions documentation and linked to such a repository in the bug description'
+        - 'I have explained in the description why a minimal reproduction is impossible'
     validations:
       required: true

.github/label-actions.yml

@@ -164,4 +164,19 @@
     Good luck,
 
 
+    The Renovate team
+
+'invalid':
+  comment: >
+    Hi there,
+
+
+    This issue has been marked as invalid and will be closed and potentially deleted too.
+    Deletion is done so that invalid issues (such as mistaken bug reports) don't show up in repository searches and confuse future users.
+
+    In future, please create _Discussions_ instead of Issues (including for the topic of this Issue if you still wish to discuss it).
+
+    Good luck,
+
+
     The Renovate team