fix(account): one form and one Save for your account; the same for an account's page in Users

Operator review of the Account page: two sections with two different
save buttons, one stuck to the next card and one beside a squeezed hint.
- Account: time zone and Email are one form; POST /account/ saves both,
  nothing unless all of it is valid. /account/email is gone.
- Users › account: Name and Email are one form; the rename route also
  saves the email switches. /settings/users/<id>/email is gone.
- The Email section is a plain section now (email_section); its hint sits
  under the switches, names the zone as the picker does, and links
  Notifications only for an admin.
- apply_email_form leaves a switch the form doesn't carry as it is.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

steward/templates/account/_email_choices.html

@@ -1,34 +1,36 @@
-{# The email form for one account (milestone 495): its address, and whether
-   it gets alert emails and the weekly report. Used by the Account page (your
-   own) and an account's page in Settings › Users (an admin's view).
-   `defaults` is {kind: bool}, the account's role defaults. #}
-{% macro email_choices(user, defaults, action, error=none, with_address=true) -%}
-<form method="post" action="{{ action }}" class="form-page" id="email">{{ csrf_field() }}
-  <section class="card form-section" aria-labelledby="email-title">
-    <h2 id="email-title" class="section-title">Email</h2>
-    {% if error %}<p class="field-error" role="alert">{{ error }}</p>{% endif %}
-    {% if with_address %}
+{# The Email section for one account (milestone 495): its address, and whether
+   it gets alert emails and the weekly report. A section of the page's one
+   form, saved by that form's Save: the Account page (your own) and an
+   account's page in Settings › Users (an admin's view, whose address sits
+   with its name). `defaults` is {kind: bool}, the account's role defaults;
+   `zone_note` says whose zone the emails' times are in. #}
+{% macro email_section(user, defaults, zone_note, with_address=true, unreachable=false) -%}
+<section class="card form-section" aria-labelledby="email-title" id="email">
+  <h2 id="email-title" class="section-title">Email</h2>
+  {% if with_address %}
+  <div class="field">
+    <label class="field-label" for="email-address">Address</label>
+    <input class="input" id="email-address" type="email" name="email" maxlength="255" value="{{ user.email }}" required>
+    {% if user.auth_source != "local" %}<span class="field-hint">Your sign-in provider set this first; change it if mail doesn't reach it.</span>{% endif %}
+  </div>
+  {% elif unreachable %}
+  <p class="field-hint tone-warn">{{ user.email }} isn't an address mail can reach, so this account gets no email. Set a real one above.</p>
+  {% endif %}
+  <div class="form-pair">
+    {% for kind, label in (("alerts", "Alert emails"), ("report", "Weekly report")) %}
+    {% set choice = user["notify_" ~ kind] %}
     <div class="field">
-      <label class="field-label" for="email-address">Address</label>
-      <input class="input" id="email-address" type="email" name="email" maxlength="255" value="{{ user.email }}" required>
-      {% if user.auth_source != "local" %}<span class="field-hint">Your sign-in provider set this first; change it if mail doesn't reach it.</span>{% endif %}
+      <label class="field-label" for="email-{{ kind }}">{{ label }}</label>
+      <select class="input" id="email-{{ kind }}" name="notify_{{ kind }}">
+        <option value=""{% if choice is none %} selected{% endif %}>As for {{ user.role.value }}s ({{ "on" if defaults[kind] else "off" }})</option>
+        <option value="on"{% if choice is sameas true %} selected{% endif %}>On</option>
+        <option value="off"{% if choice is sameas false %} selected{% endif %}>Off</option>
+      </select>
     </div>
-    {% endif %}
-    <div class="form-pair">
-      {% for kind, label in (("alerts", "Alert emails"), ("report", "Weekly report")) %}
-      {% set choice = user["notify_" ~ kind] %}
-      <div class="field">
-        <label class="field-label" for="email-{{ kind }}">{{ label }}</label>
-        <select class="input" id="email-{{ kind }}" name="notify_{{ kind }}">
-          <option value=""{% if choice is none %} selected{% endif %}>As for {{ user.role.value }}s ({{ "on" if defaults[kind] else "off" }})</option>
-          <option value="on"{% if choice is sameas true %} selected{% endif %}>On</option>
-          <option value="off"{% if choice is sameas false %} selected{% endif %}>Off</option>
-        </select>
-      </div>
-      {% endfor %}
-    </div>
-    <span class="field-hint">Times in these emails are in {{ user.time_zone or "UTC" }}. A role's default is set in Settings › Notifications.</span>
-    <button type="submit" class="btn btn-ghost">Save email settings</button>
-  </section>
-</form>
+    {% endfor %}
+  </div>
+  <p class="field-hint">Times in these emails are in {{ zone_note }}.
+    {% if session.user_role == "admin" %}Each role's default is set in Settings › <a href="/settings/notifications/">Notifications</a>.
+    {%- else %}An admin sets each role's default.{% endif %}</p>
+</section>
 {%- endmacro %}