Add bug report issue template

.github/ISSUE_TEMPLATE/bug_report.yml

@@ -0,0 +1,55 @@
+name: Bug report
+description: Report a reproducible bug
+title: "[Bug]: "
+labels: ["bug"]
+body:
+  - type: textarea
+    id: summary
+    attributes:
+      label: Summary
+      description: What happened?
+      placeholder: A clear and concise description of the bug.
+    validations:
+      required: true
+
+  - type: textarea
+    id: expected
+    attributes:
+      label: Expected behavior
+      placeholder: What did you expect to happen?
+    validations:
+      required: true
+
+  - type: textarea
+    id: steps
+    attributes:
+      label: Steps to reproduce
+      description: Provide steps so others can reproduce the issue.
+      placeholder: |
+        1.
+        2.
+        3.
+    validations:
+      required: true
+
+  - type: textarea
+    id: logs
+    attributes:
+      label: Logs / screenshots
+      description: Paste relevant logs or screenshots (remove secrets).
+      placeholder: Paste here...
+    validations:
+      required: false
+
+  - type: textarea
+    id: environment
+    attributes:
+      label: Environment
+      description: OS, Docker version, client (reth/geth/nethermind), network (mainnet/sepolia), etc.
+      placeholder: |
+        OS:
+        Docker:
+        Client:
+        Network:
+    validations:
+      required: true