fix: move spam handlers to separate groups to fix anti-spam regression

[rezhajulio]

In PTB v20+, only the first matching handler per group runs. handle_inline_keyboard_spam (group=0) consumed all group messages, preventing handle_new_user_spam and handle_duplicate_spam from ever executing — introduced in 02d0967.

Changes:

• Move each spam handler to its own group (1, 2, 3) so they all independently process every group message
• Move handle_message (profile check) to group=4
• Add ApplicationHandlerStop to handle_new_user_spam on violations to prevent later groups from processing deleted spam
• Use >= instead of == for violation threshold to handle edge cases with concurrent updates or DB race conditions