fix(admin): CredsPane 单卡保存不再联动重置兄弟卡

旧 array-source watch 盯 [emailGroup, pushGroup, aiGroup] 三元数组——任一
组引用变化即 resetAll 三卡齐重建：单卡保存（如 email）后父层 onPaneSaved
换整份快照引用，push/ai 卡上未保存的编辑被静默丢弃（Task 14 评审挂账）。

改为三表各自 watch 本组 props 引用：父层保存回写是 {...snapshot, [group]:
config} 展开——只有被保存组引用换新，兄弟组引用不动 → 只重建该卡；切租户/
回滚时快照先置 null 再整份换新，三组引用齐变 → 三卡全量重置（行为保持）。
resetAll 相应拆为 resetEmailCard / resetPushCard / resetAiCard（备注/错误/
测试态随所属卡重置）。

自查两场景：改 email 保存 → push 草稿与 dirty 均保留；切租户 → 三卡齐重置。

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

admin/src/views/config/center/CredsPane.vue

@@ -411,7 +411,8 @@
     (e: 'dirty', value: boolean): void
   }>()
 
-  // ---- 编辑态（组引用变化 = 保存回写/租户切换/重载 → 重置表单与密钥态） ----------------
+  // ---- 编辑态（单组引用变化 = 该卡保存回写/重载 → 只重置该卡；切租户/回滚时
+  // 父层整份快照换新 → 三组引用齐变 → 三卡各自重置） ------------------------------------
 
   const emailForm = reactive<EmailCredsForm>(normalizeEmailCredsGroup(undefined).form)
   const pushForm = reactive<PushCredsForm>(normalizePushCredsGroup(undefined).form)
@@ -434,8 +435,8 @@
   const emailError = ref('')
   const pushError = ref('')
   const aiError = ref('')
-  /** dirty 基线（三表单各自 normalize*Group().form 的 JSON 快照——与
-   * resetAll 同 watch 刷新；密钥输入不进基线：掩码 GET 本就无原值可比，
+  /** dirty 基线（三表单各自 normalize*Group().form 的 JSON 快照——随各组
+   * watch 刷新；密钥输入不进基线：掩码 GET 本就无原值可比，
    * 由 dirty 计算里的三态判定补足） */
   const emailBaseline = ref(JSON.stringify(normalizeEmailCredsGroup(undefined).form))
   const pushBaseline = ref(JSON.stringify(normalizePushCredsGroup(undefined).form))
@@ -453,44 +454,50 @@
   const pushProbe = ref<PushTestResponse | null>(null)
   const pushProbeError = ref('')
 
-  function resetAll(
-    emailGroup: Record<string, unknown> | null | undefined,
-    pushGroup: Record<string, unknown> | null | undefined,
-    aiGroup: Record<string, unknown> | null | undefined
-  ): void {
+  /** 单卡重置：只重建该卡的表单/密钥态/备注/错误/测试态——单卡保存回写
+   * 不再联动丢弃兄弟卡未保存草稿（Task 14 评审挂账，Task 15 修复） */
+  function resetEmailCard(emailGroup: Record<string, unknown> | null | undefined): void {
     const es = normalizeEmailCredsGroup(emailGroup)
     Object.assign(emailForm, es.form)
     emailPasswordMasked.value = es.passwordMasked
     emailPasswordCleared.value = false
     emailBaseline.value = JSON.stringify(es.form)
+    emailComment.value = ''
+    emailError.value = ''
+    emailTestResult.value = null
+    emailTesting.value = false
+  }
+
+  function resetPushCard(pushGroup: Record<string, unknown> | null | undefined): void {
     const ps = normalizePushCredsGroup(pushGroup)
     Object.assign(pushForm, ps.form)
     pushApiKeyMasked.value = ps.apiKeyMasked
     pushApiKeyCleared.value = false
     pushBaseline.value = JSON.stringify(ps.form)
-    const as = normalizeAiCredsGroup(aiGroup)
-    Object.assign(aiForm, as.form)
-    aiApiKeyMasked.value = as.apiKeyMasked
-    aiApiKeyCleared.value = false
-    aiBaseline.value = JSON.stringify(as.form)
-    emailComment.value = ''
     pushComment.value = ''
-    aiComment.value = ''
-    emailError.value = ''
     pushError.value = ''
-    aiError.value = ''
-    emailTestResult.value = null
-    emailTesting.value = false
     pushProbe.value = null
     pushProbeError.value = ''
     pushProbing.value = false
   }
 
-  watch(
-    () => [props.emailGroup, props.pushGroup, props.aiGroup],
-    ([emailGroup, pushGroup, aiGroup]) => resetAll(emailGroup, pushGroup, aiGroup),
-    { immediate: true }
-  )
+  function resetAiCard(aiGroup: Record<string, unknown> | null | undefined): void {
+    const as = normalizeAiCredsGroup(aiGroup)
+    Object.assign(aiForm, as.form)
+    aiApiKeyMasked.value = as.apiKeyMasked
+    aiApiKeyCleared.value = false
+    aiBaseline.value = JSON.stringify(as.form)
+    aiComment.value = ''
+    aiError.value = ''
+  }
+
+  // 分组 watch（替代旧 array-source 全量 resetAll）：父层 onPaneSaved 对快照做
+  // {...snapshot, [group]: config} 展开——只有被保存组引用换新，兄弟组引用不动
+  // → 只重建该卡；切租户/回滚时快照先置 null 再整份换新，三组引用齐变 → 三卡
+  // 全量重置（保持既有行为）
+  watch(() => props.emailGroup, resetEmailCard, { immediate: true })
+  watch(() => props.pushGroup, resetPushCard, { immediate: true })
+  watch(() => props.aiGroup, resetAiCard, { immediate: true })
 
   /** 未保存判定：三表单任一偏离基线，或密钥三态（输入非空 = 覆盖新值 /
    * cleared = 显式清除）——密钥输入框基线恒空串，只能独立判定 */