Bundle E: Mechanical sweeps & defensive polish — 6 findings closed; L-004 deferred

Closes L-009 + L-010 + L-011 + L-013 + L-020 + L-021 from
comprehensive-audit-2026-04-25. L-004 deferred — recon found NO
rotation infrastructure exists at all; building it from scratch is
a feature project, not a Bundle-E mechanical sweep.

L-009 — ZeroSSL EAB URL configurable
  Audit's 'no timeout' claim was wrong: ari.go:329 has 15s timeout.
  internal/connector/issuer/acme/acme.go: zeroSSLEABEndpoint now
  lazily reads CERTCTL_ZEROSSL_EAB_URL from env at package init;
  defaults to ZeroSSL public endpoint. Pre-existing test override
  path preserved.

L-010 — Verified-already-clean
  grep -rn 'mock\.Anything' --include='*_test.go' . returned 0.
  certctl uses hand-rolled struct mocks (mockJobRepo, mockAuditRepo,
  etc.) with explicit method bodies; no testify-style mocks anywhere.

L-011 — IPv6 bracket-aware dialing pinned
  Every production net.Dial / DialTimeout site audited:
    cmd/agent/main.go:293 — intentional IPv4 literal '8.8.8.8:80'
    verify.go / tlsprobe / network_scan — net.Dialer (no string addr)
    email.go — net.JoinHostPort (bracket-aware)
    ssh.go — addr derives from JoinHostPort upstream
    ssrf.go — net.Dialer
  internal/connector/notifier/email/email_ipv6_test.go (NEW):
    TestJoinHostPort_IPv6BracketsRoundTrip pins IPv4/IPv6/zone variants;
    TestSMTPDialerUsesJoinHostPort source-greps email.go and fails CI
    if a future refactor swaps in 'host:port' concatenation.

L-013 — Verified-already-clean (monotonic-safe)
  Only one site uses now.Sub: middleware.go:393 in tokenBucket.allow().
  Both 'now' and tb.lastRefill come from time.Now() which carries
  monotonic-clock readings per Go's time package contract;
  intra-process now.Sub is monotonic-safe by construction. Doc
  comment block added above the call to make the invariant explicit.

L-020 (CWE-563) — ineffassign sweep, 8 unique sites
  certificate.go:135 — sortDir initial value dropped (set
    unconditionally below by SortDesc branch).
  certificate.go:169,175 — argCount post-increments dropped (var
    not read past the LIMIT/OFFSET formatting).
  agent_group.go, profile.go — page/perPage truly vestigial,
    replaced with _ = page; _ = perPage.
  issuer.go:633, owner.go:131, target.go:267, team.go:131 — same
    treatment for the audit-flagged second-function ListXxx clamps.
  First-function List() in issuer/owner/target/team KEEPS its
    clamp because page/perPage is used for in-memory slice
    pagination — ineffassign correctly didn't flag those.
  Build + tests green post-sweep.

L-021 — Transitive CVE bump
  go get golang.org/x/crypto@v0.45.0 golang.org/x/net@v0.47.0
    (crypto required net@0.47.0). go-text@v0.31.0 transitively
    bumped.
  Per tool-output govulncheck-verbose: x/net@v0.45.0 fixes
    GO-2026-4441 + GO-2026-4440; x/crypto@v0.45.0 fixes
    GO-2025-4134 + GO-2025-4135 + GO-2025-4116 — all 5 advisories
    cleared. Bundle B's ISV grep guard + Bundle D's release-time
    govulncheck step are the going-forward monitor + bump pass.

L-004 — Deferred to dedicated bundle
  Recon: zero hits for RotateAPIKey / rotated_at / key_status
    anywhere in source. API keys configured via
    CERTCTL_API_KEYS_NAMED env var; rotation is operator-managed
    (edit env + restart). Building rotation infrastructure from
    scratch is a feature project, not a mechanical sweep.
  Documented in audit-report.md with scope-pivot note.

Audit deliverables:
  audit-report.md: score 46/55 -> 52/55 closed
    (Low 14/19 -> 19/19 — 100% Low closed except L-004 deferred)
  findings.yaml: 6 status flips
  certctl/CHANGELOG.md: Bundle E section

Verification:
  go test -count=1 -short ./internal/service ./internal/connector/issuer/acme
    ./internal/connector/notifier/email                      green
  go vet on changed packages                                  clean

go.sum

@@ -196,6 +196,8 @@ golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5y
 golang.org/x/crypto v0.6.0/go.mod h1:OFC/31mSvZgRz0V1QTNCzfAI1aIRzbiufJtkMIlEp58=
 golang.org/x/crypto v0.41.0 h1:WKYxWedPGCTVVl5+WHSSrOBT0O8lx32+zxmHxijgXp4=
 golang.org/x/crypto v0.41.0/go.mod h1:pO5AFd7FA68rFak7rOAGVuygIISepHftHnr8dr6+sUc=
+golang.org/x/crypto v0.45.0 h1:jMBrvKuj23MTlT0bQEOBcAE0mjg8mK9RXFhRH6nyF3Q=
+golang.org/x/crypto v0.45.0/go.mod h1:XTGrrkGJve7CYK7J8PEww4aY7gM3qMCElcJQ8n8JdX4=
 golang.org/x/mod v0.2.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.3.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
@@ -210,6 +212,8 @@ golang.org/x/net v0.6.0/go.mod h1:2Tu9+aMcznHK/AK1HMvgo6xiTLG5rD5rZLDS+rp2Bjs=
 golang.org/x/net v0.7.0/go.mod h1:2Tu9+aMcznHK/AK1HMvgo6xiTLG5rD5rZLDS+rp2Bjs=
 golang.org/x/net v0.42.0 h1:jzkYrhi3YQWD6MLBJcsklgQsoAcw89EcZbJw8Z614hs=
 golang.org/x/net v0.42.0/go.mod h1:FF1RA5d3u7nAYA4z2TkclSCKh68eSXtiFwcWQpPXdt8=
+golang.org/x/net v0.47.0 h1:Mx+4dIFzqraBXUugkia1OOvlD6LemFo1ALMHjrXDOhY=
+golang.org/x/net v0.47.0/go.mod h1:/jNxtkgq5yWUGYkaZGqo27cfGZ1c5Nen03aYrrKpVRU=
 golang.org/x/oauth2 v0.34.0 h1:hqK/t4AKgbqWkdkcAeI8XLmbK+4m4G5YeQRrmiotGlw=
 golang.org/x/oauth2 v0.34.0/go.mod h1:lzm5WQJQwKZ3nwavOZ3IS5Aulzxi68dUSgRHujetwEA=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
@@ -238,12 +242,15 @@ golang.org/x/term v0.0.0-20210927222741-03fcf44c2211/go.mod h1:jbD1KX2456YbFQfuX
 golang.org/x/term v0.5.0/go.mod h1:jMB1sMXY+tzblOD4FWmEbocvup2/aLOaQEp7JmGp78k=
 golang.org/x/term v0.34.0 h1:O/2T7POpk0ZZ7MAzMeWFSg6S5IpWd/RXDlM9hgM3DR4=
 golang.org/x/term v0.34.0/go.mod h1:5jC53AEywhIVebHgPVeg0mj8OD3VO9OzclacVrqpaAw=
+golang.org/x/term v0.37.0 h1:8EGAD0qCmHYZg6J17DvsMy9/wJ7/D/4pV/wfnld5lTU=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
 golang.org/x/text v0.7.0/go.mod h1:mrYo+phRRbMaCq/xk9113O4dZlRixOauAjOtrjsXDZ8=
 golang.org/x/text v0.28.0 h1:rhazDwis8INMIwQ4tpjLDzUhx6RlXqZNPEM0huQojng=
 golang.org/x/text v0.28.0/go.mod h1:U8nCwOR8jO/marOQ0QbDiOngZVEBB7MAiitBuMjXiNU=
+golang.org/x/text v0.31.0 h1:aC8ghyu4JhP8VojJ2lEHBnochRno1sgL6nEi9WGFGMM=
+golang.org/x/text v0.31.0/go.mod h1:tKRAlv61yKIjGGHX/4tP1LTbc13YSec1pxVEWXzfoeM=
 golang.org/x/time v0.0.0-20220210224613-90d013bbcef8 h1:vVKdlvoWBphwdxWKrFZEuM0kGgGLxUOYcY4U/2Vjg44=
 golang.org/x/time v0.0.0-20220210224613-90d013bbcef8/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=