feat: enhance admin and contact components with new functionality

- Updated `AdminPage` to conditionally display duty reassignment instructions based on visible groups, improving user guidance.
- Refactored `AdminDutyList` to streamline the display of duties, enhancing visual clarity and organization.
- Introduced `openPhoneLink` and `triggerHapticLight` functions in `ContactLinks` for improved phone link interaction and haptic feedback.
- Added unit tests for `openPhoneLink` to ensure correct functionality and handling of various phone number formats.
- Enhanced existing tests for `ContactLinks` to verify new phone link behavior, ensuring robust testing coverage.

webapp-next/src/lib/open-phone-link.ts

@@ -0,0 +1,46 @@
+/**
+ * Opens a phone number for calling. Uses native tel: navigation so the OS
+ * or WebView can open the dialer. Does not use Telegram openLink() for tel:
+ * (protocol is not supported; it closes the app on desktop and does nothing on mobile).
+ */
+
+/**
+ * Builds a tel: URL from a phone string (digits and optional leading + only).
+ */
+function buildTelUrl(phone: string): string {
+  const trimmed = String(phone).trim();
+  if (trimmed === "") return "";
+  const digits = trimmed.replace(/\D/g, "");
+  if (digits.length === 11 && (digits[0] === "7" || digits[0] === "8")) {
+    return `tel:+7${digits.slice(1)}`;
+  }
+  if (digits.length === 10) {
+    return `tel:+7${digits}`;
+  }
+  return `tel:${trimmed.startsWith("+") ? "+" : ""}${digits}`;
+}
+
+/**
+ * Opens the given phone number for calling. Tries window.open(telUrl) first
+ * (reported to work for tel: in some Telegram WebViews), then a programmatic
+ * click on a temporary tel: link. openLink(tel:) is not used — Telegram does
+ * not support it (closes app on desktop, no dialer on mobile). Safe to call
+ * from click handlers; does not throw.
+ */
+export function openPhoneLink(phone: string | null | undefined): void {
+  if (phone == null || String(phone).trim() === "") return;
+  const telUrl = buildTelUrl(phone);
+  if (telUrl === "") return;
+  if (typeof window === "undefined" || !window.document) return;
+
+  const opened = window.open(telUrl);
+  if (opened !== null) return;
+
+  const anchor = window.document.createElement("a");
+  anchor.href = telUrl;
+  anchor.style.display = "none";
+  anchor.setAttribute("aria-hidden", "true");
+  window.document.body.appendChild(anchor);
+  anchor.click();
+  anchor.remove();
+}