refactor(i18n): U29 phantom key 全项目清零 — 28 个 phantom key → 0

AlertRuleDialog.tsx (9处) + DeployTargetFields.tsx (3处) + HealthProbeSection.tsx (2处+1处硬编码) + PodLogsViewer.tsx (2处终端ANSI字符串) + AlertChannelDialog.tsx (2处) + PodMetricsPage.tsx/CapacityPage.tsx (各1处) + PodExecTerminal.tsx (1处终端ANSI) + BuildNodesManager.tsx (1处) + HostDetailDialog.tsx (1处)

修复类型:
- 批量正则损坏的 i18n.t('>中文 <span className=') → 语义化键
- 终端 ANSI 转义字符串 (PodLogsViewer/PodExecTerminal) → 移除 i18n.t() 包裹改纯字符串
- 硬编码中文 (取消/通知渠道提示/日志数据源提示) → i18n.t() 调用

新增 16 个翻译键 (monitor.alertRuleDialog2.* + monitor.alertChannel.name + agent.portCount + monitor.lbl.noProbeHint)
zh/en 7358→7375 +17 键对齐
phantom key 28→0 (全项目零 phantom key)
tsc -b=0, npm build✓ (17.00s), ESLint=0/53/0, go build=0, 17/17 测试通过

frontend/src/components/kubernetes/CapacityPage.tsx

@@ -121,7 +121,7 @@ export default function CapacityPage() {
             </TableRow></TableHeader>
             <TableBody>
               {rows.length === 0 ? (
-                <TableRow><TableCell colSpan={8} className="text-center dg-text-muted py-8">{i18n.t('>暂无数据{loading ? <span className=')}</TableCell></TableRow>
+                <TableRow><TableCell colSpan={8} className="text-center dg-text-muted py-8">{i18n.t('common.noData')}</TableCell></TableRow>
               ) : rows.map((r, i) => (
                 <TableRow key={`${r.deployment}-${r.container}-${i}`} className="border-[var(--dg-border)] hover:bg-[var(--dg-bg-hover)]">
                   <TableCell className="font-medium text-[var(--dg-text-primary)] text-sm">{r.deployment}</TableCell>