v0.2.6

Added

• TorPoolProxyUrl: support for tor-pool,
  which fronts many Tor instances with one sticky SOCKS port. The SOCKS5
  username is a session key, so a scrape keeps the same exit IP until it
  rotates; rotation goes through the pool's API and skips Tor's ~10s NEWNYM
  cooldown by reassigning to an already-built instance.

  Set token to a proxy-scoped token from the pool — it is required by
  tor-pool 0.2 and later, and is sent both as the SOCKS5 password and as a
  bearer token on the pool's API. Without it the pool answers 401, and because
  those calls are best-effort the failure would otherwise pass as a warning while
  the pool quietly stopped hearing about soft blocks; that specific case is
  logged at error instead.

• ProxyManager.report_failure(): reports 403s, challenges, rate limits and
  transport errors to the pool. This is the only signal that catches a soft block
  — a proxy relaying bytes cannot see a 403 or a captcha inside an HTTPS tunnel —
  and it is what lets the pool quarantine a burnt exit. Sent automatically by the
  engine; call it directly when your own code detects a block.

  The pool weighs a report by what it says went wrong, so each one carries a
  kind as well as free text. A 429 that no challenge handler claimed is sent as
  rate_limited rather than as a generic failure: a throttle says the exit works
  and is being asked for too much, and reported as a block it would retire a
  working exit while the next one is throttled just the same.

• scraper.engine.proxy_manager.FAILURE_KINDS, the mapping from a failure reason
  to the kind sent alongside it. Reasons the engine raises itself are all
  covered, as is the pool's own
  vocabulary for callers passing it straight through; anything else is still
  reported and the pool counts it as unclassified. Sent explicitly rather than
  left to the pool to read out of the free text — its aliases exist for callers
  written before kinds did, so leaning on them means a vocabulary drift on either
  side quietly downgrades every report to unremarkable.

• examples/13_tor_pool.py.

Fixed

• Rotating a proxy now drops pooled connections. A live keep-alive stays bound
  to its original exit, so without this the exit IP appeared not to change until
  the socket happened to be evicted.
• A pool that no longer knows a session is no longer a warning. Acting on a
  report, the pool takes the instance out of rotation and unpins its sessions, so
  the next report about that session answers 404 — routine, and the next
  request re-pins to a healthy instance, but it logged a warning per report for
  exactly the exit that was failing most.