init: arcadia-admin — admin webapp for arcadia-core, cloned from vibespace

Initial commit. Spun up via the docs/STARTER.md recipe: cp from vibespace,
reset git, rename package, set brand to "Arcadia Admin" with Shield icon
in app/lib/identity.ts.

Inherits the full Crema sibling-lib wiring including @crema/arcadia-client
(typed HTTP + Phoenix Channels realtime against arcadia-core) and
@crema/arcadia-auth-ui (login/signup/password-reset/2FA forms). The /login
route already renders <LoginForm>; <ArcadiaProvider> in app/root.tsx reads
VITE_ARCADIA_URL (default localhost:4000) and VITE_ARCADIA_TENANT (default
"default").

CLAUDE.md and README rewritten to frame this as the admin app for
arcadia-core. docs/STARTER.md removed — arcadia-admin is a leaf consumer,
not a downstream starter.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

app/components/ui/alert.tsx

@@ -0,0 +1,76 @@
+import * as React from "react"
+import { cva, type VariantProps } from "class-variance-authority"
+
+import { cn } from "~/lib/utils"
+
+const alertVariants = cva(
+  "group/alert relative grid w-full gap-0.5 rounded-lg border px-2.5 py-2 text-left text-sm has-data-[slot=alert-action]:relative has-data-[slot=alert-action]:pr-18 has-[>svg]:grid-cols-[auto_1fr] has-[>svg]:gap-x-2 *:[svg]:row-span-2 *:[svg]:translate-y-0.5 *:[svg]:text-current *:[svg:not([class*='size-'])]:size-4",
+  {
+    variants: {
+      variant: {
+        default: "bg-card text-card-foreground",
+        destructive:
+          "bg-card text-destructive *:data-[slot=alert-description]:text-destructive/90 *:[svg]:text-current",
+      },
+    },
+    defaultVariants: {
+      variant: "default",
+    },
+  }
+)
+
+function Alert({
+  className,
+  variant,
+  ...props
+}: React.ComponentProps<"div"> & VariantProps<typeof alertVariants>) {
+  return (
+    <div
+      data-slot="alert"
+      role="alert"
+      className={cn(alertVariants({ variant }), className)}
+      {...props}
+    />
+  )
+}
+
+function AlertTitle({ className, ...props }: React.ComponentProps<"div">) {
+  return (
+    <div
+      data-slot="alert-title"
+      className={cn(
+        "font-heading font-medium group-has-[>svg]/alert:col-start-2 [&_a]:underline [&_a]:underline-offset-3 [&_a]:hover:text-foreground",
+        className
+      )}
+      {...props}
+    />
+  )
+}
+
+function AlertDescription({
+  className,
+  ...props
+}: React.ComponentProps<"div">) {
+  return (
+    <div
+      data-slot="alert-description"
+      className={cn(
+        "text-sm text-balance text-muted-foreground md:text-pretty [&_a]:underline [&_a]:underline-offset-3 [&_a]:hover:text-foreground [&_p:not(:last-child)]:mb-4",
+        className
+      )}
+      {...props}
+    />
+  )
+}
+
+function AlertAction({ className, ...props }: React.ComponentProps<"div">) {
+  return (
+    <div
+      data-slot="alert-action"
+      className={cn("absolute top-2 right-2", className)}
+      {...props}
+    />
+  )
+}
+
+export { Alert, AlertTitle, AlertDescription, AlertAction }