fix: sweep D3 amendment through the specs; correct inverted DKIM table

The re-audit of the deploy-guard change surfaced defects well outside the
diff, including one that would have broken production mail.

docs/05-backend-spec.md had the two SES DKIM sets exactly inverted, labelling
the three records that resolve as "orphans" and the three NXDOMAIN records as
"Live. Never delete". Entry (j) corrected this in AGENTS.md §7 and the
correction never reached docs/05. Since SES has no custom MAIL FROM, DKIM is
the only thing satisfying DMARC, so acting on that table would have silently
broken intake mail authentication.

Also in this change:

- .gitea/workflows/deploy.yml gains a guard as steps[0] that fails the run,
  naming the variable, if AWS_REGION, S3_BUCKET or CLOUDFRONT_DISTRIBUTION_ID
  is empty — how a Gitea too old for the vars context manifests. Verified
  fail-closed under bash -e, sh -e and bash -euo pipefail.
- AGENTS.md Current Truth: SPF and DMARC recorded as present (Q20), the
  matching §10 High risk row retired, three duplicate Q rows removed.
- docs/reference/AWS-Hosting-Guide.md tracked and given a do-not-execute
  banner; it was an executable procedure for the architecture D1/D3 replace.
- Copy decks: "a working litigator" and "an active litigation practice"
  replaced with the register's own wording; LegalService JSON-LD replaced with
  ProfessionalService; tribunal-secretary offers removed per D14; nine stale
  question blockers swept.
- astro.config.mjs: prefetchAll disabled — it injected JS into every page
  against the zero-JS convention with no decision recorded.
- src/data/site.ts: unregistered response-time commitment nulled (Q27);
  OBA section names downgraded to [assumed] (Q28).
- s3:AbortMultipartUpload reasoning corrected to measure ./dist, not the repo.

Opens Q27, Q28, Q29. AGENTS.md entry (q) records the full resolution,
including the findings declined and why.

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

.claude/commands/build.md

@@ -19,7 +19,7 @@ does not apply, say which and why before moving on.
    Reminders** and surface anything live to Pouya before you start.
 2. Read the specs in `docs/` that bear on this task.
 3. Restate the task in your own words, and name:
-   - which locked decisions (D1–D16) it touches
+   - which locked decisions (D1–D18) it touches
    - which specs govern it
    - which facts it needs from the §4 Verified register
 4. **Stop and ask if you find a conflict** — between the task and a locked
@@ -87,5 +87,10 @@ why, and any decision or plan — including declined findings and anything
 deferred. Update Current Truth in place where the change made a section stale.
 Re-stamp facts you re-checked with today's date.
 
+**If the entry claims a change was applied across files, cite the command and
+paste its output.** Write that claim only after reading the output. Recall is
+not evidence — three entries on this project asserted a completed sweep and
+instances survived all three.
+
 Then report to Pouya: what shipped, what the review found, what you declined and
 why, and what remains open.