fix(engine): ensure stats safely handles getter errors and invalid timeRemaining values

[kaiserc]

Summary

This PR improves the resilience of \TorrentEngine.stats()\ when querying WebTorrent statistics on initializing or errored torrents.

Changes Made

• Wrapped property reads inside \stats()\ to catch WebTorrent getter exceptions before metadata finishes parsing.
• Added explicit validation for \ imeRemaining\ so non-numeric / \NaN\ / \undefined\ values fall back cleanly to \Infinity.

Verification

• All 280 unit tests pass via
  px vitest run.