feat(ui): redesign the overview page as a trend-first command deck

Replace the ten-small-cards overview with an action bar, four vitals
tiles carrying 72-sample sparklines seeded from /server/history, a
two-series throughput chart, a TCP/UDP connections chart, and a
grouped system strip (uptime xray|os, panel ram|threads, ip
addresses). StatusCard and XrayStatusCard are deleted; every modal
stays reachable from the action bar, the Xray error message moves
into a tooltip on the state pill, and the panel version text keeps
opening the update modal (the dev-channel switch lives there) even
when no update is available. Live values sit beside the
upload/download and tcp/udp legends, a health sentence appears only
when a vital crosses the shared warn/crit thresholds now exported
from models/status, and load average is left to System History.

The sidebar becomes an auto-collapsed 72px icon rail that expands as
an overlay on hover: rail width, brand-row height and menu paddings
are pinned so nothing shifts during the transition, the collapsed-menu
tooltips are disabled, hover state survives the per-page sidebar
remounts (with a matches(':hover') resync), and the manual collapse
trigger is gone.

Sparkline gains rgb()/rgba() support in its fill gradient, a
showLegend prop so pages stop reaching into its internals, and loses
a dependency-less repaint effect that doubled canvas paints. Chart
tooltips show clock time via the new TimeFormatter.formatClock;
accents come from theme tokens instead of status.cpu.color. Verified
by screenshot at 390/800/1150/1280/1400/1600px in light and dark,
en and fa-IR, plus programmatic geometry checks on the sidebar.
Locale files gain 8 keys and lose 9 dead ones across all 13
languages.

internal/web/translation/zh-TW.json

@@ -106,7 +106,6 @@
     "routing": "路由",
     "outbounds": "出站",
     "apiDocs": "API 文件",
-    "link": "管理",
     "donate": "捐贈",
     "hosts": "Hosts",
     "docs": "文件",
@@ -127,12 +126,9 @@
     },
     "index": {
       "cpu": "CPU",
-      "logicalProcessors": "邏輯處理器",
-      "frequency": "頻率",
       "swap": "交換空間",
       "storage": "儲存",
       "memory": "記憶體",
-      "threads": "執行緒",
       "xrayStatus": "Xray",
       "stopXray": "停止",
       "restartXray": "重新啟動",
@@ -153,7 +149,6 @@
       "xrayStatusRunning": "運行中",
       "xrayStatusStop": "停止",
       "xrayStatusError": "錯誤",
-      "operationHours": "系統正常執行時間",
       "systemHistoryTitle": "系統歷史",
       "historyTitleCpu": "CPU 使用率",
       "historyTitleMem": "記憶體使用率",
@@ -171,7 +166,6 @@
       "historyTabLoad": "負載",
       "historyTabConnections": "連線數",
       "historyTabDiskUsage": "磁碟使用量",
-      "charts": "圖表",
       "xrayMetricsTitle": "Xray 指標",
       "xrayTitleHeap": "已配置的堆積記憶體",
       "xrayTitleSys": "向作業系統保留的記憶體",
@@ -200,7 +194,6 @@
       "overallSpeed": "整體速度",
       "upload": "上傳",
       "download": "下載",
-      "totalData": "總數據",
       "sent": "已發送",
       "received": "已接收",
       "xraySwitchVersionDialog": "您確定要變更 Xray 版本嗎？",
@@ -250,7 +243,18 @@
       "exportDatabasePgDesc": "點擊將目前資料庫的 PostgreSQL 傾印（.dump）下載到您的裝置。",
       "importDatabasePgDesc": "點擊選擇並上傳 PostgreSQL 備份（.dump）、SQLite 資料庫（.db）或 SQLite 遷移匯出檔以還原您的資料庫。此操作將取代所有目前的資料。",
       "migrationDownload": "下載遷移檔案",
-      "migrationDownloadPgDesc": "點擊下載由 PostgreSQL 資料建立的 .db SQLite 資料庫，可用於在 SQLite 上執行本面板。"
+      "migrationDownloadPgDesc": "點擊下載由 PostgreSQL 資料建立的 .db SQLite 資料庫，可用於在 SQLite 上執行本面板。",
+      "avg": "均值",
+      "peak": "峰值",
+      "free": "剩餘",
+      "openSockets": "開啟的通訊端",
+      "throughputSub": "網路介面總計",
+      "avgWindow": "視窗均值",
+      "healthWarm": "{list} — 偏高",
+      "healthCritical": "{list} — 危險",
+      "panel": "面板",
+      "threads": "執行緒",
+      "uptime": "執行時間"
     },
     "inbounds": {
       "totalDownUp": "總上傳 / 下載",