fix(admin): sidebar invisible (CSS specificity) + /admin lands on dashboard

- AdminShell: the rtl:/ltr: translate variants ([dir] selector) out-specified
  lg:translate-x-0, so the sidebar stayed off-screen on desktop and the mobile
  drawer couldn't open. Pin physically right + plain translate-x-full/0; content
  uses lg:mr-60.
- /admin now redirects to /admin/stats (overview) instead of /admin/nodes.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/app/[locale]/admin/page.tsx

@@ -1,5 +1,6 @@
 import { redirect } from "next/navigation";
 
 export default function AdminRootPage() {
-  redirect("/admin/nodes");
+  // Land on the dashboard overview, not an arbitrary section.
+  redirect("/admin/stats");
 }

src/components/admin/AdminShell.tsx

@@ -28,10 +28,13 @@ export function AdminShell({
 
   return (
     <div className="min-h-screen bg-[#0c0e1a] text-gray-200">
-      {/* Sidebar */}
+      {/* Sidebar — pinned to the right (admin is RTL-primary). lg:translate-x-0
+          keeps it visible on desktop; on mobile it slides off the right edge.
+          (Avoid rtl:/ltr: translate variants — their [dir] selector out-specifies
+          lg: and would keep the panel off-screen.) */}
       <aside
-        className={`fixed inset-y-0 start-0 z-40 flex w-60 flex-col border-e border-[#1e2235] bg-[#0d0f1c] transition-transform lg:translate-x-0 ${
-          open ? "translate-x-0" : "rtl:translate-x-full ltr:-translate-x-full"
+        className={`fixed inset-y-0 right-0 z-40 flex w-60 flex-col border-l border-[#1e2235] bg-[#0d0f1c] transition-transform lg:translate-x-0 ${
+          open ? "translate-x-0" : "translate-x-full"
         }`}
       >
         <div className="flex h-14 items-center gap-2 border-b border-[#1e2235] px-5">
@@ -75,7 +78,7 @@ export function AdminShell({
       {open && <div className="fixed inset-0 z-30 bg-black/50 lg:hidden" onClick={() => setOpen(false)} />}
 
       {/* Main column */}
-      <div className="lg:ms-60">
+      <div className="lg:mr-60">
         <header className="sticky top-0 z-20 flex h-14 items-center gap-3 border-b border-[#1e2235] bg-[#0f1120]/90 px-5 backdrop-blur">
           <button
             className="rounded-lg border border-[#262b40] p-1.5 text-gray-300 hover:bg-[#161a2e] lg:hidden"