Hold the issuer-website-unreachable messages to the consistency rules #34

What

The consistency suite holds every combination of check results to the wording rules: no reassurance in a "couldn't check", no registry named to the earner, no talk of expiry outside "Expired", and so on. But its signature dimension (Sig in test/consistency-combinations.ts) has no case for an issuer website that can't be reached. So did_web_unresolved and http_error_with_signature_check (src/outcomes.ts, reported by verifier-core as DID_WEB_UNRESOLVED and HTTP_ERROR on the signature check) never come out of it, their own wording is never checked, and their rows in the suite's expectations table are dead.

Found in the final review of #31: appending "It's probably fine." to did_web_unresolved's detail fails 0 of 105,713 tests. Today's wording is fine; this is about catching a future rewording. It predates #31.

Proposed fix

Add the two signature failures to Sig, built as verifier-core 2.0.0-beta.1 reports them, and treat them like the other failed seals (SIG_FATAL). The reviewer tried this: the suite passes as it stands (about 156,000 tests), and the mutation above then fails 13,440. Then mutation-check that each rule now bites for these outcomes, and that the suite stays well inside Vitest's time limits.

Not in scope

Changing either message's wording.