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/es-ES.json

@@ -106,7 +106,6 @@
     "routing": "Enrutamiento",
     "outbounds": "Salidas",
     "apiDocs": "Documentación de la API",
-    "link": "Gestionar",
     "donate": "Donar",
     "hosts": "Hosts",
     "docs": "Documentación",
@@ -127,12 +126,9 @@
     },
     "index": {
       "cpu": "CPU",
-      "logicalProcessors": "Procesadores lógicos",
-      "frequency": "Frecuencia",
       "swap": "Swap",
       "storage": "Almacenamiento",
       "memory": "Memoria",
-      "threads": "Hilos",
       "xrayStatus": "Xray",
       "stopXray": "Detener",
       "restartXray": "Reiniciar",
@@ -153,7 +149,6 @@
       "xrayStatusRunning": "En ejecución",
       "xrayStatusStop": "Detenido",
       "xrayStatusError": "Error",
-      "operationHours": "Tiempo de Funcionamiento",
       "systemHistoryTitle": "Historial del Sistema",
       "historyTitleCpu": "Uso de CPU",
       "historyTitleMem": "Uso de Memoria",
@@ -171,7 +166,6 @@
       "historyTabLoad": "Carga",
       "historyTabConnections": "Conexiones",
       "historyTabDiskUsage": "Uso de Disco",
-      "charts": "Gráficos",
       "xrayMetricsTitle": "Métricas de Xray",
       "xrayTitleHeap": "Memoria Heap Asignada",
       "xrayTitleSys": "Memoria Reservada del SO",
@@ -200,7 +194,6 @@
       "overallSpeed": "Velocidad general",
       "upload": "Subida",
       "download": "Descargar",
-      "totalData": "Datos totales",
       "sent": "Enviado",
       "received": "Recibido",
       "xraySwitchVersionDialog": "¿Realmente deseas cambiar la versión de Xray?",
@@ -250,7 +243,18 @@
       "exportDatabasePgDesc": "Haz clic para descargar un volcado de PostgreSQL (.dump) de tu base de datos actual en tu dispositivo.",
       "importDatabasePgDesc": "Haz clic para seleccionar y subir una copia de seguridad de PostgreSQL (.dump), una base de datos SQLite (.db) o un volcado de migración de SQLite para restaurar tu base de datos. Esto reemplaza todos los datos actuales.",
       "migrationDownload": "Descargar migración",
-      "migrationDownloadPgDesc": "Haz clic para descargar una base de datos SQLite .db creada a partir de tus datos de PostgreSQL, lista para ejecutar este panel en SQLite."
+      "migrationDownloadPgDesc": "Haz clic para descargar una base de datos SQLite .db creada a partir de tus datos de PostgreSQL, lista para ejecutar este panel en SQLite.",
+      "avg": "media",
+      "peak": "pico",
+      "free": "libre",
+      "openSockets": "sockets abiertos",
+      "throughputSub": "Total de la interfaz",
+      "avgWindow": "Media del periodo",
+      "healthWarm": "{list} — algo elevado",
+      "healthCritical": "{list} — crítico",
+      "panel": "Panel",
+      "threads": "Hilos",
+      "uptime": "Tiempo activo"
     },
     "inbounds": {
       "totalDownUp": "Subidas/Descargas Totales",