Add footer; default to public explorers (proxy via localStorage opt-in)

- Footer: "made with ♥ by Adam Soltys" (links adamsoltys.com) and "source
  available on GitHub" (links the repo).
- Explorer endpoint now defaults to the public explorers; a rate-limited
  machine can opt into a proxy via localStorage('explorer-proxy'). Correct for
  a hosted multi-user deploy (each visitor uses their own IP).

Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>

3 files changed, 29 insertions, 4 deletions

diff --git a/src/api.js b/src/api.js
index 0135369..a91d94b 100644
--- a/src/api.js
+++ b/src/api.js
@@ -6,9 +6,18 @@
 //   - a 429 from ANY request immediately backs off ALL subsequent requests
 //     (global exponential pause), easing back as requests succeed.
 
-// TEMPORARY: route explorer traffic through a VPS while this IP is rate-limited
-// by mempool.space. Set PROXY = '' to go back to the public explorers directly.
-const PROXY = 'http://51.79.52.200:8088';
+// Explorer endpoint. Defaults to the public explorers (correct for a hosted,
+// multi-user deploy — each visitor uses their own IP). A specific machine whose
+// IP is rate-limited can opt into a proxy at runtime:
+//   localStorage.setItem('explorer-proxy', 'http://51.79.52.200:8088')
+// (http proxy only works when the page itself is served over http/localhost).
+const PROXY = (() => {
+  try {
+    return localStorage.getItem('explorer-proxy') || '';
+  } catch {
+    return '';
+  }
+})();
 
 const BACKENDS = PROXY
   ? {
diff --git a/src/app.js b/src/app.js
index e59b1bd..a017841 100644
--- a/src/app.js
+++ b/src/app.js
@@ -73,8 +73,21 @@ function h(tag, attrs = {}, ...children) {
 }
 
 const root = document.getElementById('app');
+function footer() {
+  return h(
+    'div',
+    { class: 'footer small muted center' },
+    'made with ',
+    h('span', { style: 'color:#e25555' }, '♥'),
+    ' by ',
+    h('a', { href: 'https://adamsoltys.com', target: '_blank', rel: 'noopener' }, 'Adam Soltys'),
+    h('span', { class: 'faint' }, ' · '),
+    h('a', { href: 'https://github.com/asoltys/cold', target: '_blank', rel: 'noopener' }, 'source available on GitHub')
+  );
+}
+
 function render() {
-  root.replaceChildren(ui.screen === 'wallet' ? walletScreen() : unlockScreen());
+  root.replaceChildren(ui.screen === 'wallet' ? walletScreen() : unlockScreen(), footer());
 }
 wallet.subscribe(render);
 
diff --git a/src/style.css b/src/style.css
index 2d11662..160cca2 100644
--- a/src/style.css
+++ b/src/style.css
@@ -208,6 +208,9 @@ textarea { resize: vertical; min-height: 84px; font-family: var(--mono); font-si
 .toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }
 .words .w.masked .t { color: var(--faint); letter-spacing: 2px; }
 
+.footer { margin-top: 28px; padding-bottom: 8px; }
+.footer a { color: var(--accent-ink); font-weight: 600; }
+
 /* Clickable unit labels (BTC/sats) — look like text, toggle the global unit. */
 .unit-tag {
   background: none; border: 0; padding: 0; margin: 0; font: inherit; cursor: pointer;