docs(e2e): correct stale spec counts in the workflow's comments

WHY THIS MATTERS
Two comments in .github/workflows/e2e.yml still said a keyless run
"passes the other 23 specs". That was true of an earlier revision of
this branch, but the suite has since grown (4 accessibility specs were
added): it now has 31 specs, of which 4 are LLM-gated, so a keyless run
passes 27. Stale numbers in CI comments are worse than no numbers: a
maintainer eyeballing a green keyless run against the comment ("23
passed? but I see 27...") is left wondering whether extra specs
accidentally ran with a leaked key, or whether the skip mechanism is
broken - the comment turns a healthy run into a false alarm. The
companion doc (docs/e2e-ci.md) already states 31/27; the workflow now
agrees with it.

WHAT IS COMMENT DRIFT
Comments are not checked by any compiler or test, so they rot silently
when the code they describe changes - here, the spec count changed in a
later commit on the same branch and nothing forced the comment to keep
up. The practical defenses are (a) keeping numbers in as few places as
possible and pointing everywhere else at that one place, and (b)
sweeping comments whenever the quantity they cite changes. This commit
applies (b); both comments also point at docs/e2e-ci.md, which remains
the authoritative source for expected pass/skip totals.

HOW THE FIX WORKS
Pure comment edits, no behavioral change:

- the workflow header now reads "of the 31 specs, the 4 LLM-dependent
  ones ... skip themselves ... so a keyless run passes the other 27
  specs";
- the ANTHROPIC_API_KEY env comment now reads "still green on the other
  27 of the 31 specs".

Verified the file still YAML-parses (python3 -c "import yaml;
yaml.safe_load(...)") and that `CI=1 npx playwright test --list`
reports "Total: 31 tests", matching the corrected figures.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>