release: 0.1.0: Phases 0-11: panel, Postfix/DKIM, milter, backup, Docker image

Initial feature-complete implementation of the v1.0 specification (phases 0-11 of `docs/implementation-plan.md`).
Added:
  - Panel (Go, single static binary) with SQLite persistence, one-time
  - Domain management with per-domain DKIM (RSA-2048, generated in pure Go) and
  - Application (sender identity) management: SASL credentials via `sasldb2`,
  - Full Postfix relay config generated from env at container start: SMTPS 465,
  - Journal milter (pure Go, `go-milter`) recording every send to `send_log`;
  … (6 more in CHANGELOG)

Full detail: CHANGELOG.md (0.1.0).

test/e2e/sink/Dockerfile

@@ -0,0 +1,26 @@
+# SMTP sink-MX for the e2e stand (plan C.4): accepts any mail on 25 and dumps
+# each transaction to its own file under /mail, so the test harness can read
+# the raw received message (headers + body, including the DKIM-Signature
+# Postfix/OpenDKIM added) straight off disk. smtp-sink ships in the postfix
+# package itself — no new dependency.
+FROM debian:bookworm-slim
+
+ENV DEBIAN_FRONTEND=noninteractive
+RUN echo "postfix postfix/mailname string localhost" | debconf-set-selections \
+ && echo "postfix postfix/main_mailer_type string Internet Site" | debconf-set-selections \
+ && apt-get update \
+ && apt-get install -y --no-install-recommends postfix \
+ && rm -rf /var/lib/apt/lists/*
+
+RUN mkdir -p /mail
+WORKDIR /mail
+
+# -d: one file per transaction (a pseudo-random suffix is appended
+# automatically), so the harness just watches the directory for a new file
+# instead of parsing a shared multi-message dump. Binding :25 needs root, and
+# smtp-sink refuses to run as root without an explicit -u to switch to after
+# binding — "-u root" satisfies that check while staying root throughout,
+# which is fine here: throwaway container, isolated e2e network, never
+# exposed.
+ENTRYPOINT ["/usr/sbin/smtp-sink"]
+CMD ["-u", "root", "-d", "/mail/%Y%m%d%H%M%S.", "0.0.0.0:25", "100"]