Add Telegram notifications

src/static/admin.js

@@ -725,6 +725,52 @@ document.getElementById("chpw-form").addEventListener("submit", async e => {
   }
 });
 
+// ── Telegram / Notifications ──────────────────────────────────────────────────
+async function loadTelegram() {
+  try {
+    const cfg = await api("GET", "/api/admin/telegram");
+    document.getElementById("tg-chat-id").value = cfg.chat_id || "";
+    document.getElementById("tg-enabled").checked = cfg.enabled;
+    document.getElementById("tg-status").textContent = cfg.configured
+      ? "Bot token is saved. Leave the token field empty to keep it."
+      : "Not configured yet. Enter a bot token to get started.";
+  } catch { /* non-admin: tab hidden anyway */ }
+}
+
+document.getElementById("telegram-form").addEventListener("submit", async e => {
+  e.preventDefault();
+  const token = document.getElementById("tg-token").value.trim() || null;
+  const chat_id = document.getElementById("tg-chat-id").value.trim();
+  const enabled = document.getElementById("tg-enabled").checked;
+  const errEl = document.getElementById("tg-error");
+  errEl.classList.add("hidden");
+  try {
+    await api("PUT", "/api/admin/telegram", { bot_token: token, chat_id, enabled });
+    document.getElementById("tg-token").value = "";
+    showToast("Telegram settings saved");
+    loadTelegram();
+  } catch (e) {
+    errEl.textContent = e.message;
+    errEl.classList.remove("hidden");
+  }
+});
+
+document.getElementById("btn-tg-test").addEventListener("click", async () => {
+  const btn = document.getElementById("btn-tg-test");
+  const errEl = document.getElementById("tg-error");
+  btn.disabled = true;
+  errEl.classList.add("hidden");
+  try {
+    await api("POST", "/api/admin/telegram/test");
+    showToast("Test message sent ✓");
+  } catch (e) {
+    errEl.textContent = e.message;
+    errEl.classList.remove("hidden");
+  } finally {
+    btn.disabled = false;
+  }
+});
+
 // ── Load all data ─────────────────────────────────────────────────────────────
 function loadAllData() {
   const isAdmin = _tokenPayload().scope === "admin";
@@ -734,6 +780,7 @@ function loadAllData() {
   if (isAdmin) {
     loadCredentials();
     loadAdmins();
+    loadTelegram();
   }
 }