feat(release): rebase PR branch before updating changelog

When updating an existing release PR, the workflow now rebases
the next-release branch onto the base branch using Gitea's PR
update API with style=rebase. This keeps the PR up to date with
main without force-pushing or deleting the branch.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

.claude/settings.local.json

@@ -2,7 +2,10 @@
   "permissions": {
     "allow": [
       "Bash(but --help:*)",
-      "Bash(but rub --help:*)"
+      "Bash(but rub --help:*)",
+      "WebSearch",
+      "WebFetch(domain:docs.gitea.com)",
+      "WebFetch(domain:gitea.com)"
     ]
   }
 }

.gitea/workflows/Release.yml

@@ -100,6 +100,22 @@ jobs:
             "${API_URL}/pulls?state=open" | jq '[.[] | select(.head.ref == "next-release")]')
           PR_INDEX=$(echo "${PRS}" | jq -r '.[0].number // empty')
 
+          # If PR exists, rebase the branch onto the latest base branch
+          if [ -n "${PR_INDEX}" ]; then
+            echo "Rebasing PR #${PR_INDEX} branch onto ${BASE_BRANCH}..."
+            REBASE_RESPONSE=$(curl -s -w "\n%{http_code}" -X POST \
+              -H "Authorization: token ${TOKEN}" \
+              "${API_URL}/pulls/${PR_INDEX}/update?style=rebase")
+            REBASE_CODE=$(echo "${REBASE_RESPONSE}" | tail -1)
+            if [ "${REBASE_CODE}" = "200" ]; then
+              echo "Successfully rebased branch onto ${BASE_BRANCH}"
+            elif [ "${REBASE_CODE}" = "409" ]; then
+              echo "Branch already up to date or rebase conflict - continuing with update"
+            else
+              echo "Warning: Rebase returned ${REBASE_CODE}, continuing anyway"
+            fi
+          fi
+
           echo "Checking for existing next-release branch..."
           BRANCH_CHECK=$(curl -s -w "%{http_code}" -o /dev/null \
             -H "Authorization: token ${TOKEN}" \