feat: Reinitialize frontend with SvelteKit and TypeScript

- Delete old Vite+Svelte frontend
- Initialize new SvelteKit project with TypeScript
- Configure Tailwind CSS v4 + DaisyUI
- Implement JWT authentication with auto-refresh
- Create login page with form validation (Zod)
- Add protected route guards
- Update Docker configuration for single-stage build
- Add E2E tests with Playwright (6/11 passing)
- Fix Svelte 5 reactivity with $state() runes

Known issues:
- 5 E2E tests failing (timing/async issues)
- Token refresh implementation needs debugging
- Validation error display timing

frontend/node_modules/libphonenumber-js/es6/helpers/extension/extractExtension.js

@@ -0,0 +1,30 @@
+import createExtensionPattern from './createExtensionPattern.js';
+
+// Regexp of all known extension prefixes used by different regions followed by
+// 1 or more valid digits, for use when parsing.
+var EXTN_PATTERN = new RegExp('(?:' + createExtensionPattern() + ')$', 'i');
+
+// Strips any extension (as in, the part of the number dialled after the call is
+// connected, usually indicated with extn, ext, x or similar) from the end of
+// the number, and returns it.
+export default function extractExtension(number) {
+  var start = number.search(EXTN_PATTERN);
+  if (start < 0) {
+    return {};
+  }
+  // If we find a potential extension, and the number preceding this is a viable
+  // number, we assume it is an extension.
+  var numberWithoutExtension = number.slice(0, start);
+  var matches = number.match(EXTN_PATTERN);
+  var i = 1;
+  while (i < matches.length) {
+    if (matches[i]) {
+      return {
+        number: numberWithoutExtension,
+        ext: matches[i]
+      };
+    }
+    i++;
+  }
+}
+//# sourceMappingURL=extractExtension.js.map