chore: correct the review agents' briefs and add a Phase 5 minifier check

Separated from the step 1 feature commit on adversarial-reviewer's own
recommendation: instructions that narrow a reviewer's scope should not
travel in the same commit as the work that reviewer is checking.

claims-auditor.md — REMOVE the enumerated membership list. It read
"ADRIC, ADRIO, OBA sections only" while AGENTS.md §4 had gained the
Canadian Tax Foundation that morning, so the auditor's own brief
contradicted the register: it would have flagged a verified membership
as unverified and would not have noticed CTF being dropped. This file
has now hosted a stale claim twice. Replaced with an instruction to
read the §4 row at audit time — a copy of a fact goes stale where
nobody re-reads it.

adversarial-reviewer.md — state that Lighthouse cannot be run until
step 7 and that its absence is not a finding (AGENTS.md §7, R11).
Repair a sentence left truncated mid-list. Caveat the "~1 MB of logo
PNGs" figure against Q34, which is open on it.

build.md — Phase 4 now carries the measurement that justifies the
re-review requirement: on the Astro 5→7 upgrade four of six
second-round findings were defects in the first round's own fixes.
Phase 5 gains a grep asserting no `animation` shorthand beside
`animation-timeline` survives into dist — Lightning CSS folds them
into an invalid declaration that works in dev and is dead in the
build. That happened twice in one session, the second time inside the
fix for the first.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012XquaEq4BgWMCwUqLEyNkF

.claude/agents/adversarial-reviewer.md

@@ -54,10 +54,16 @@ full content with JavaScript disabled.** Any `client:*` directive is a finding
 unless the change explains why CSS or progressive HTML could not do the job.
 
 **4. Performance.** Budgets in `docs/04-seo-spec.md`: Lighthouse ≥ 95 mobile on
-all four categories, under 100 KB JS per route, LCP under 2.0 s. Check for
-base64-inlined images, images without explicit dimensions, runtime font requests,
-and third-party scripts. The old build inlined ~1 MB of logo PNGs — watch for
-regressions of that shape.
+all four categories, under 100 KB JS per route, LCP under 2.0 s.
+
+**Lighthouse itself cannot be run right now** — `@lhci/cli` was removed on
+2026-08-26 and returns at build step 7 (`AGENTS.md` §7, R11). So do not report
+"Lighthouse not run" as a finding; it is a known, recorded gap. Review
+everything that *would* move those numbers by reading the artefact instead:
+base64-inlined images, images without explicit dimensions, runtime font
+requests, and third-party scripts. The old build is *said* to have inlined ~1 MB
+of logo PNGs — `AGENTS.md` Q34 is open against that figure, so watch for
+regressions of that shape without repeating the number as fact.
 
 **5. Security and data handling.** Any hardcoded endpoint, key, or credential is
 a finding. Check CSP compatibility, that form input is validated server-side and