i18n(panel): migrate hardcoded panel strings to en-US and translate all locales

Surface ~400 hardcoded English labels, tooltips, placeholders, dt/divider
text, modal okText/cancelText, and Spin loading from the panel pages
(clients/groups/inbounds/nodes/settings/xray/sub/index) into
web/translation/en-US.json under existing pages.<page>.* namespaces, with
JSX swapped to t(...). Brand and protocol identifiers (TLS, MTU, SNI,
NordVPN, Cloudflare WARP, etc.) stay literal.

Sync all 12 non-English locales (ar-EG, es-ES, fa-IR, id-ID, ja-JP,
pt-BR, ru-RU, tr-TR, uk-UA, vi-VN, zh-CN, zh-TW) to match en-US's
structure and translate the 521 new key paths per locale. Every locale
file now has 1539 lines, mirroring en-US ordering.

Also remove a dead duplicate "info": "Info" key under pages.inbounds
that collided with the new pages.inbounds.info.* object.

Backend: bulk attach/detach errors in web/service/client.go now route
through logger.Warningf (so they appear under /panel/api/server/logs/)
instead of only living on the response payload.

frontend/src/pages/xray/OutboundsTab.tsx

@@ -258,7 +258,7 @@ export default function OutboundsTab({
         ),
       },
       {
-        title: 'Tag',
+        title: t('pages.xray.outbound.tag'),
         key: 'identity',
         align: 'left',
         render: (_v, record) => (
@@ -316,7 +316,7 @@ export default function OutboundsTab({
         },
       },
       {
-        title: 'Latency',
+        title: t('pages.nodes.latency'),
         key: 'testResult',
         align: 'left',
         width: 140,
@@ -398,14 +398,14 @@ export default function OutboundsTab({
           </Col>
           <Col xs={24} sm={12} className="toolbar-right">
             <Space size="small" wrap>
-              <Tooltip title="TCP: fast dial-only probe. HTTP: full request through xray.">
+              <Tooltip title={t('pages.xray.outbound.testModeTooltip')}>
                 <Radio.Group value={testMode} onChange={(e) => setTestMode(e.target.value)} buttonStyle="solid" size="small">
                   <Radio.Button value="tcp">TCP</Radio.Button>
                   <Radio.Button value="http">HTTP</Radio.Button>
                 </Radio.Group>
               </Tooltip>
               <Button type="primary" loading={testingAll} icon={<PlayCircleOutlined />} onClick={() => onTestAll(testMode)}>
-                {!isMobile && 'Test all'}
+                {!isMobile && t('pages.xray.outbound.testAll')}
               </Button>
               <Popconfirm
                 placement="topRight"