No longer needed since the scrubber is not memoized across calls and the
text node length guard prevents the performance issue.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
A large comment body was causing Regexp::TimeoutError in production.
The URI regexp isn't catastrophically backtracking — it's linear — but
with a long enough string it exceeds the 1s Regexp.timeout set by
Rails.
Skip scanning text nodes over 10KB, which is well beyond any
reasonable content for auto-linking and still keeps us many orders of
magnitued under the timeout on an unloaded machine.
Fixes FIZZY-Q4
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Instead, let's use a Loofah scrubber which will create DOM nodes
directly. This should be faster and is a tiny bit simpler, as well as
removing a potential HTML injection vector.
Also, add "noreferrer" to all `mailto:` links (already present on URLs).