fix+upstream: hooks-order crash, ConfirmDialog/PageHeader/skeletons, styled error boundary

Hoists hooks above early return (render-time Navigate); ports finance's
ConfirmDialog/PageHeader/loading/states + APC error-copy mapper; removes
window.confirm, dead appbar search, and seeded fake notifications; wires toasts.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

app/components/layout/page-header.tsx

@@ -0,0 +1,36 @@
+import { type ReactNode } from "react"
+
+interface PageHeaderProps {
+  title: ReactNode
+  description?: ReactNode
+  /** Inline indicators after the title (badges, status pills). */
+  badges?: ReactNode
+  /** Toolbar rendered below the title row — primary actions go here. */
+  actions?: ReactNode
+}
+
+// Shared page header for the app's main surfaces. Keeps the title/description
+// pattern consistent across routes so forks don't reinvent it per page.
+export function PageHeader({
+  title,
+  description,
+  badges,
+  actions,
+}: PageHeaderProps) {
+  return (
+    <header className="flex flex-col gap-3">
+      <div className="flex flex-wrap items-end gap-4">
+        <h1 className="text-headline font-semibold tracking-tight">{title}</h1>
+        {badges}
+      </div>
+      {description ? (
+        <p className="max-w-2xl text-[15px] leading-relaxed text-muted-foreground">
+          {description}
+        </p>
+      ) : null}
+      {actions ? (
+        <div className="mt-2 flex flex-wrap items-center gap-2">{actions}</div>
+      ) : null}
+    </header>
+  )
+}