Add NIP-05 badges, hashtag pages, keyword muting, suggestion dismissal, notification poller

- Article cover: aspect-video replaces max-h-72 for consistent 16:9
- NIP-05 verification badge on note cards with 1-hour TTL cache
- Dedicated hashtag feed pages (clicking #tag opens live feed, not search)
- Keyword muting: word-boundary matching, applied across all feed views
- Follow suggestion dismissal: persistent "don't suggest again" per person
- Background notification poller (60s): mentions, zaps, new followers
- All notification types independently toggleable in settings
- Centralized notification firing (removed inline store notifications)

src/hooks/useNip05Verified.ts

@@ -0,0 +1,51 @@
+import { useState, useEffect } from "react";
+
+type VerifyStatus = "valid" | "invalid";
+
+const cache = new Map<string, { status: VerifyStatus; checkedAt: number }>();
+const TTL = 3600000; // 1 hour
+
+async function verifyNip05(pubkey: string, nip05: string): Promise<VerifyStatus> {
+  const parts = nip05.split("@");
+  if (parts.length !== 2) return "invalid";
+  const [name, domain] = parts;
+  try {
+    const res = await fetch(`https://${domain}/.well-known/nostr.json?name=${encodeURIComponent(name)}`);
+    if (!res.ok) return "invalid";
+    const json = await res.json();
+    const resolved = json?.names?.[name];
+    return resolved === pubkey ? "valid" : "invalid";
+  } catch {
+    return "invalid";
+  }
+}
+
+export function useNip05Verified(pubkey: string, nip05: string | undefined): "valid" | "invalid" | "checking" | null {
+  const [status, setStatus] = useState<"valid" | "invalid" | "checking" | null>(() => {
+    if (!nip05) return null;
+    const cached = cache.get(pubkey);
+    if (cached && Date.now() - cached.checkedAt < TTL) return cached.status;
+    return "checking";
+  });
+
+  useEffect(() => {
+    if (!nip05) { setStatus(null); return; }
+
+    const cached = cache.get(pubkey);
+    if (cached && Date.now() - cached.checkedAt < TTL) {
+      setStatus(cached.status);
+      return;
+    }
+
+    let cancelled = false;
+    setStatus("checking");
+    verifyNip05(pubkey, nip05).then((result) => {
+      if (cancelled) return;
+      cache.set(pubkey, { status: result, checkedAt: Date.now() });
+      setStatus(result);
+    });
+    return () => { cancelled = true; };
+  }, [pubkey, nip05]);
+
+  return status;
+}