Use Telegram Login Widget for web auth

Dockerfile

@@ -2,14 +2,14 @@ FROM ghcr.io/cirruslabs/flutter:stable AS build
 WORKDIR /app
 ARG MAPBOX_ACCESS_TOKEN=""
 ARG MAPBOX_STYLE="mapbox/streets-v12"
-ARG TELEGRAM_BOT_URL="https://t.me/carfteebot"
+ARG TELEGRAM_BOT_USERNAME="carfteebot"
 COPY pubspec.* ./
 RUN flutter pub get
 COPY . .
 RUN flutter build web --release \
   --dart-define=MAPBOX_ACCESS_TOKEN="$MAPBOX_ACCESS_TOKEN" \
   --dart-define=MAPBOX_STYLE="$MAPBOX_STYLE" \
-  --dart-define=TELEGRAM_BOT_URL="$TELEGRAM_BOT_URL"
+  --dart-define=TELEGRAM_BOT_USERNAME="$TELEGRAM_BOT_USERNAME"
 
 FROM nginx:1.27-alpine
 COPY nginx.conf /etc/nginx/conf.d/default.conf