Move the PoW state from a module-level dict keyed by WebSocket in
messages.py to a plain per-connection local in tracking.activity_ws,
making PoW a WS-level concern instead of being buried in the message
handler:
- activity_ws validates and burns the solution (raw.pop('pow')) before
forwarding a message frame, and issues a fresh challenge after every
registration and every vetted message frame; a failed validation is
answered with a 'required' challenge and the frame never reaches
messages.py.
- messages.py loses the _pow dict, _issue_pow and the disconnect
cleanup for it; visitor_frame needs no return value since a vetted
frame always triggers a fresh challenge (a too-long message simply
comes with contact-error and required=false, so the client does not
retry it).
The wire protocol and the frontend are unchanged.
LeoVasanko
e3080d70c0