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).

internal/web/templates/setup.html

@@ -0,0 +1,20 @@
+{{define "content"}}
+<h1>Create administrator</h1>
+<div class="card narrow">
+  <p class="muted">This one-time link creates the single panel administrator.
+  After you submit, the link stops working for good.</p>
+  {{if .Error}}<p class="error">{{.Error}}</p>{{end}}
+  <form method="post" action="/setup/{{.Token}}">
+    <label for="username">Username</label>
+    <input id="username" name="username" autocomplete="username" autofocus required>
+
+    <label for="password">Password</label>
+    <input id="password" name="password" type="password" autocomplete="new-password" required>
+
+    <label for="password_confirm">Confirm password</label>
+    <input id="password_confirm" name="password_confirm" type="password" autocomplete="new-password" required>
+
+    <button type="submit">Create administrator</button>
+  </form>
+</div>
+{{end}}