9de34900a2
Bot uses default HTML parse mode — all messages are HTML-parsed by Telegram. Added html.escape() to all user-controlled and admin-controlled strings before interpolation into HTML messages to prevent injection and parse errors. 49 files, ~250+ injection points fixed: - user.full_name, first_name across all handlers and services - tariff.name/description in purchase flow, admin panel, auto-purchase service - campaign.name, start_parameter in admin and user-facing handlers - group.name, promo_group.name across promo management - contest.title, prize_text, leaderboard names (including public channels) - transaction.description (contains raw user.full_name from referral service) - restriction_reason across all balance and subscription handlers - ticket.title, message_text, poll.title, poll.description - welcome text template placeholders (first_name, username) - maintenance reason, admin_name, selected_prize.display_name New helpers in app/utils/formatting.py: - safe_html_name() for escaping display names - user_html_link() replacing 15+ duplicated inline link patterns