Compare the sender's user id (not the chat id, which only matches in
private chats) and require the bot to actually be an admin with post
rights instead of silently passing when it is missing from the list.
Also stops panicking on get_me network failures.
Call setMyCommands at startup so clients show the command list in the
/ menu. handlers::register_commands wraps Command::bot_commands()
(teloxide derives it from the #[command(description)] attributes);
a registration failure only warns and does not stop the bot.
/clear_cache with no argument wipes the whole link_cache table;
with a post URL it removes that single entry (normalized via
site::cache_key so fxtwitter/mobile/photo variants collide with
the write-side key). Non-admins get 'Admin only.'. LinkCache gains
clear(Option<&str>) -> usize reporting removed rows.
All bot commands now carry English descriptions, shown in the Telegram
command menu and by /help (which prints Command::descriptions()). The
README command table explains each command's arguments and behavior:
forward channel (@channel or ID), edit-before-forward flow, template
[] placeholder semantics and per-site caption format placeholders.