Legal pages (Terms, Privacy, Disclaimer) + always-present footer

- New /terms, /privacy, /disclaimer pages in the site style with real content
  tailored to an on-chain ad+referral platform (no income guarantee, crypto
  risk, rehearsal note, privacy of email/wallet/profile, acceptable use).
- renderNav now appends a persistent footer with legal + site links on every
  public page; member-area sidebar gets a Legal link group.

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

public/assets/common.js

@@ -45,6 +45,17 @@ window.IAP = (function () {
     const a = nav.querySelector('[data-p="' + active + '"]');
     if (a) a.className = 'active';
     refreshNavWallet();
+    renderFooter();
+  }
+  function renderFooter() {
+    if (document.getElementById('iapFooter')) return;
+    const f = document.createElement('footer'); f.id = 'iapFooter';
+    f.style.cssText = 'border-top:1px solid var(--line);margin-top:48px;padding:26px 22px;text-align:center;color:var(--muted);font-size:13px';
+    f.innerHTML = '<div>© ' + new Date().getFullYear() + ' InstantAdPay</div>'
+      + '<div style="margin-top:8px;display:flex;gap:16px;justify-content:center;flex-wrap:wrap">'
+      + '<a href="/">How it works</a><a href="/ledger">Live ledger</a><a href="/contract">The contract</a>'
+      + '<a href="/terms">Terms</a><a href="/privacy">Privacy</a><a href="/disclaimer">Disclaimer</a></div>';
+    document.body.appendChild(f);
   }
   async function refreshNavWallet() {
     try {

public/assets/legal.js

@@ -0,0 +1,2 @@
+// legal/static content pages: render the shared nav + footer
+(async function () { try { await IAP.renderNav(''); } catch (e) {} })();