fix(ci): auto-merge从轮询长作业改为短作业模式

- auto_merge.sh: 去掉90次x30秒的轮询循环，改为单次检查
- 超时从45分钟缩短为3分钟
- CI未通过/未就绪时直接退出，不占用Runner
- 由pr-auto-scan每5分钟定时扫描兜底，CI通过后自动合并
- 保留405重试机制（单次运行内最多3次）

问题：auto-merge job轮询等待CI通过，最长占Runner 45分钟，资源浪费。
修复：改为短作业模式——检查一次CI状态，满足就合并，不满足就退出。
兜底：pr-auto-scan.yml每5分钟扫描所有open PR，CI全绿的自动审批+合并。

.gitea/workflows/pr-automation.yml

@@ -56,7 +56,7 @@ jobs:
     name: Auto Merge on CI Green + Approved
     runs-on: ci-check
     if: github.event_name == 'pull_request' && !github.event.pull_request.draft && github.event.pull_request.base.ref == 'develop'
-    timeout-minutes: 45  # 长等待模式：等CI全绿后自动合并，不遗漏任何PR
+    timeout-minutes: 3  # 短作业模式：检查一次，不满足就退出，由pr-auto-scan每5分钟定时兜底
     steps:
       - name: Checkout code
         shell: sh

scripts/ci/auto_merge.sh

@@ -1,5 +1,6 @@
 #!/usr/bin/env bash
 # 自动合并：CI全绿+已审批后自动squash merge PR到develop
+# 短作业模式：只检查一次，不满足条件就退出，由pr-auto-scan定时兜底
 # 环境变量：GITHUB_TOKEN, MERGE_TOKEN, PR_NUMBER, PR_HEAD_SHA, BASE_REF, GITHUB_API_URL, GITHUB_REPOSITORY
 set -eu
 
@@ -7,6 +8,8 @@ set -eu
 
 echo "PR #${PR_NUMBER} - 检查CI状态+审批并自动合并到${BASE_REF}"
 echo
+echo "模式: 短作业（只检查一次，不满足则退出，由pr-auto-scan定时兜底）"
+echo
 
 # 只合develop分支
 if [ "$BASE_REF" != "develop" ]; then
@@ -30,21 +33,20 @@ CONTEXTS=(
 echo "检查CI Gate统一门禁"
 echo
 
-# 初始等待30秒，给CI启动写status的时间
-echo "等待30秒让CI启动..."
-sleep 30
+# 等待60秒，给CI启动写status的时间
+echo "等待60秒让CI启动..."
+sleep 60
 
-# 405连续计数器
+# 405计数器（单次运行内重试）
 MERGE_405_COUNT=0
-MAX_405_RETRIES=10
+MAX_405_RETRIES=3
 
-# 轮询等待，最多30分钟（180次x10秒）
-for attempt in $(seq 1 90); do  # 最多等45分钟(90次x30秒)，确保等得到Worker构建完成
+check_and_merge() {
   ALL_SUCCESS=true
   ANY_FAILED=false
   ANY_PENDING=false
 
-  echo "--- 第${attempt}次检查 ($(date '+%H:%M:%S')) ---"
+  echo "--- 检查CI状态 ($(date '+%H:%M:%S')) ---"
 
   # 检查CI状态
   for ctx in "${CONTEXTS[@]}"; do
@@ -61,77 +63,82 @@ for attempt in $(seq 1 90); do  # 最多等45分钟(90次x30秒)，确保等得
     fi
   done
 
-
-  # CI全绿 → 合并
-  if [ "$ALL_SUCCESS" = "true" ]; then
-    echo
-    echo "CI全绿，执行自动合并"
-    echo "等待60秒冷却，给Gitea内部状态同步时间..."
-    sleep 60
-
-    # 幂等检查：PR是否还是open
-    PR_STATE=$(curl -s -H "Authorization: token ${MERGE_TOKEN}" \
-      "${GITHUB_API_URL}/repos/${GITHUB_REPOSITORY}/pulls/${PR_NUMBER}" \
-      | python3 -c "import sys,json; print(json.load(sys.stdin).get('state',''))")
-
-    if [ "$PR_STATE" != "open" ]; then
-      echo "PR状态为 ${PR_STATE}，无需合并"
-      exit 0
-    fi
-
-    # 执行squash merge
-    HTTP_CODE=$(curl -s -o /tmp/merge_resp.json -w "%{http_code}" \
-      -X POST \
-      -H "Authorization: token ${MERGE_TOKEN}" \
-      -H "Content-Type: application/json" \
-      -d '{"do":"squash","merge_title_field":"","merge_message_field":"","delete_branch_after_merge":true,"force_merge":false}' \
-      "${GITHUB_API_URL}/repos/${GITHUB_REPOSITORY}/pulls/${PR_NUMBER}/merge")
-
-    echo "合并API HTTP状态: $HTTP_CODE"
-
-    if [ "$HTTP_CODE" = "200" ]; then
-      echo "自动合并成功"
-      exit 0
-    elif [ "$HTTP_CODE" = "405" ]; then
-      MERGE_405_COUNT=$((MERGE_405_COUNT + 1))
-      echo "⚠️  合并返回405（第${MERGE_405_COUNT}次），可能CI状态尚未同步或有未解决的门禁，继续等待重试..."
-      cat /tmp/merge_resp.json 2>/dev/null || true
-      echo
-      if [ "$MERGE_405_COUNT" -ge "$MAX_405_RETRIES" ]; then
-        echo "⚠️  连续${MAX_405_RETRIES}次合并返回405，放弃自动合并（需人工确认，非代码问题）"
-        curl -s -X POST \
-          -H "Authorization: token ${MERGE_TOKEN}" \
-          -H "Content-Type: application/json" \
-          -d '{"body": "Auto merge skipped after multiple 405 errors: PR may have conflicts or unresolved checks. Please review manually. This is not a CI failure."}' \
-          "${GITHUB_API_URL}/repos/${GITHUB_REPOSITORY}/issues/${PR_NUMBER}/comments" > /dev/null 2>&1 || true
-        exit 0
-      fi
-      sleep 30
-      continue
-    else
-      echo "自动合并失败 (HTTP $HTTP_CODE)"
-      cat /tmp/merge_resp.json 2>/dev/null || true
-      curl -s -X POST \
-        -H "Authorization: token ${MERGE_TOKEN}" \
-        -H "Content-Type: application/json" \
-        -d "{\"body\": \"Auto merge failed (HTTP ${HTTP_CODE}), please check manually.\"}" \
-        "${GITHUB_API_URL}/repos/${GITHUB_REPOSITORY}/issues/${PR_NUMBER}/comments" > /dev/null 2>&1 || true
-      exit 1
-    fi
-  else
-    # 本轮不满足合并条件，重置405计数器
-    MERGE_405_COUNT=0
-  fi
-
+  # CI有失败 → 不合并，直接退出
   if [ "$ANY_FAILED" = "true" ]; then
     echo
-    echo "CI有失败项，不自动合并"
+    echo "❌ CI有失败项，不自动合并"
     exit 0
   fi
 
+  # CI未全绿（pending中）→ 退出，等下次触发
+  if [ "$ALL_SUCCESS" != "true" ]; then
+    echo
+    echo "⏳ CI尚未全绿（仍有pending），退出等待下次触发"
+    echo "   （pr-auto-scan每5分钟扫描一次，CI通过后会自动合并）"
+    exit 0
+  fi
+
+  # CI全绿 → 合并
+  echo
+  echo "✅ CI全绿，执行自动合并"
+  echo "等待30秒冷却，给Gitea内部状态同步时间..."
   sleep 30
+
+  # 幂等检查：PR是否还是open
+  PR_STATE=$(curl -s -H "Authorization: token ${MERGE_TOKEN}" \
+    "${GITHUB_API_URL}/repos/${GITHUB_REPOSITORY}/pulls/${PR_NUMBER}" \
+    | python3 -c "import sys,json; print(json.load(sys.stdin).get('state',''))")
+
+  if [ "$PR_STATE" != "open" ]; then
+    echo "PR状态为 ${PR_STATE}，无需合并"
+    exit 0
+  fi
+
+  # 执行squash merge
+  HTTP_CODE=$(curl -s -o /tmp/merge_resp.json -w "%{http_code}" \
+    -X POST \
+    -H "Authorization: token ${MERGE_TOKEN}" \
+    -H "Content-Type: application/json" \
+    -d '{"do":"squash","merge_title_field":"","merge_message_field":"","delete_branch_after_merge":true,"force_merge":false}' \
+    "${GITHUB_API_URL}/repos/${GITHUB_REPOSITORY}/pulls/${PR_NUMBER}/merge")
+
+  echo "合并API HTTP状态: $HTTP_CODE"
+
+  if [ "$HTTP_CODE" = "200" ]; then
+    echo "✅ 自动合并成功"
+    exit 0
+  elif [ "$HTTP_CODE" = "405" ]; then
+    MERGE_405_COUNT=$((MERGE_405_COUNT + 1))
+    echo "⚠️  合并返回405（第${MERGE_405_COUNT}次），可能CI状态尚未同步或有未解决的门禁"
+    cat /tmp/merge_resp.json 2>/dev/null || true
+    echo
+    if [ "$MERGE_405_COUNT" -ge "$MAX_405_RETRIES" ]; then
+      echo "⚠️  连续${MAX_405_RETRIES}次合并返回405，放弃本次自动合并"
+      echo "   （pr-auto-scan会继续尝试，需人工确认是否有冲突或门禁问题）"
+      exit 0
+    fi
+    echo "30秒后重试..."
+    sleep 30
+    return 1  # 重试
+  else
+    echo "❌ 自动合并失败 (HTTP $HTTP_CODE)"
+    cat /tmp/merge_resp.json 2>/dev/null || true
+    curl -s -X POST \
+      -H "Authorization: token ${MERGE_TOKEN}" \
+      -H "Content-Type: application/json" \
+      -d "{\"body\": \"Auto merge failed (HTTP ${HTTP_CODE}), please check manually.\"}" \
+      "${GITHUB_API_URL}/repos/${GITHUB_REPOSITORY}/issues/${PR_NUMBER}/comments" > /dev/null 2>&1 || true
+    exit 1
+  fi
+}
+
+# 最多重试3次（用于405重试，非CI轮询）
+for i in 1 2 3; do
+  if check_and_merge; then
+    exit 0
+  fi
 done
 
 echo
-echo "快速检查超时（3分钟），CI尚未全绿或无审批，退出等待下次触发"
+echo "本次检查未满足合并条件，退出。pr-auto-scan每5分钟会继续扫描。"
 exit 0