feat: user search/discovery

Previously the only way to find someone to follow was knowing their
exact username. Add GET /api/v1/users/search (name/username ilike,
excludes blocked-either-way) and a /people page with debounced search
+ inline follow buttons. Linked from the Explore page.

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

apps/web/components/search/explore-page-content.tsx

@@ -244,7 +244,12 @@ export function ExplorePageContent({ trending, recent, initialQuery }: Props) {
     <div className="max-w-5xl mx-auto space-y-10">
       {/* Search bar */}
       <div className="space-y-3">
-        <h1 className="text-3xl font-bold">{t("title")}</h1>
+        <div className="flex items-center justify-between">
+          <h1 className="text-3xl font-bold">{t("title")}</h1>
+          <Link href="/people" className="text-sm text-muted-foreground hover:text-foreground underline underline-offset-4">
+            Find people
+          </Link>
+        </div>
         <form onSubmit={handleSubmit} className="relative">
           <Search className="absolute left-3 top-1/2 -translate-y-1/2 h-5 w-5 text-muted-foreground pointer-events-none" />
           <Input