release: 1.1.0: Domain-admin role and internal/web package split

The first MINOR after 1.0.0: send-only DMARC guidance in the panel, AGPL packaging on every page, and an internal split of `internal/web` ahead of domain-admin work. Upgrading runs one SQLite migration (empty defaults; existing DNS guidance is unchanged until you set a report address).
Changed:
  - `internal/web` split into subpackages (`web/view`, `web/auth`, `web/validate`,
Added:
  - panel: DMARC guidance for send-only relays — the suggested `_dmarc` record
  - AGPL packaging hygiene: [NOTICE](NOTICE) names the copyright holder and the
  - [docs/roadmap.md](docs/roadmap.md) — candidate item **visual-style** (panel

Full detail: CHANGELOG.md (1.1.0).

internal/web/view/templates/encrypt_fields.html

@@ -0,0 +1,24 @@
+{{/* Password fields shared by the full-backup and domain-export forms. The
+     checkbox is the switch: unticked, the download keeps its historic plain
+     form (.tar.gz / .json); ticked, the file is sealed in a password-encrypted
+     envelope (.spbk = SelfPost backup, .spde = SelfPost domain export). The
+     fields start hidden and are revealed by panel.js — with JavaScript blocked
+     they are simply always visible, and the server still decides from the
+     checkbox alone. */}}
+{{define "encryptfields"}}
+<div class="encrypt">
+  <label class="check">
+    <input type="checkbox" name="encrypt" value="1" data-encrypt-toggle>
+    <span>Encrypt with a password</span>
+  </label>
+  <div class="encrypt-fields" data-encrypt-fields>
+    <label for="encpw">Password</label>
+    <input id="encpw" name="password" type="password" autocomplete="new-password"
+           minlength="{{.MinPwLen}}" placeholder="at least {{.MinPwLen}} characters">
+    <label for="encpw2">Repeat password</label>
+    <input id="encpw2" name="password_confirm" type="password" autocomplete="new-password">
+    <p class="muted">Keep this password: without it the file cannot be opened,
+    and SelfPost does not store it anywhere.</p>
+  </div>
+</div>
+{{end}}