feat(timeline): record a change by hand from the Timeline, a host's page or MCP log_change (#6350)

A change Steward can't see happen (a config edited, a disk swapped) is
recorded by whoever made it: what was done, its area, when (in the reader's
own zone), the hosts, what it was done to and a detail. Its author or an
admin edits or deletes it; recording, editing and deleting are audited and
those audit rows stay off the timeline. log_change records one as
"<user> via MCP", editable by the token's user.

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

steward/templates/timeline/_entry.html

@@ -1,16 +1,19 @@
 {# One timeline entry's parts, shared by the Timeline page and a host's card.
    `item` is a timeline.service.view() row. #}
 
-{# What happened: its kind, the sentence, a note, and the full record while it is kept. #}
-{% macro entry_what(item) -%}
+{# What happened: its kind, the sentence, a note, and the full record while it
+   is kept; a change the reader recorded (or any, for an admin) can be edited,
+   returning to `back`. #}
+{% macro entry_what(item, back="/timeline/") -%}
 {%- set e = item.entry -%}
 <div>
   {%- if item.kind_label %}<span class="tone-dim">{{ item.kind_label }} · </span>{% endif -%}
   {{ e.summary }}
 </div>
-{%- if item.note %}<div class="field-hint">{{ item.note }}</div>{% endif %}
+{%- if item.note %}<div class="field-hint" style="white-space:pre-line;">{{ item.note }}</div>{% endif %}
 {%- if item.url %}<div class="field-hint"><a href="{{ item.url }}">Details</a></div>
 {%- elif item.gone %}<div class="field-hint">Details no longer kept</div>{% endif %}
+{%- if item.editable %}<div class="field-hint"><a href="/timeline/changes/{{ e.id }}/edit?back={{ back|urlencode }}">Edit</a></div>{% endif %}
 {%- endmacro %}
 
 {# Where: the hosts it happened on, each linked to its timeline, and what it happened to. #}

steward/templates/timeline/_host_card.html

@@ -5,7 +5,10 @@
 <section class="card" aria-labelledby="host-history">
   <div style="display:flex;align-items:baseline;justify-content:space-between;gap:1rem;">
     <h3 id="host-history" class="section-title">History</h3>
-    <a class="field-hint" href="/timeline/?host={{ host.name|urlencode }}">All of {{ host.name }}'s history</a>
+    <span class="field-hint">
+      {%- if session.user_role in ('operator', 'admin') %}<a href="/timeline/changes/new?host={{ host.name|urlencode }}&amp;back={{ ('/hosts/' ~ host.id)|urlencode }}">Record a change</a> · {% endif -%}
+      <a href="/timeline/?host={{ host.name|urlencode }}">All of {{ host.name }}'s history</a>
+    </span>
   </div>
   {% if items %}
   <table class="table">
@@ -13,7 +16,7 @@
       {% for item in items %}
       <tr>
         <td class="nowrap" style="width:1%;">{{ item.entry.at|when }}</td>
-        <td>{{ entry_what(item) }}</td>
+        <td>{{ entry_what(item, '/hosts/' ~ host.id) }}</td>
         <td class="nowrap" style="width:1%;">{{ item.entry.actor }}</td>
       </tr>
       {% endfor %}

steward/templates/timeline/_rows.html

@@ -8,7 +8,7 @@
       {% if item.opens_group %}<tr class="table-divider"><th colspan="5" scope="rowgroup">{{ item.group }}</th></tr>{% endif %}
       <tr>
         <td class="nowrap">{{ e.at|when }}</td>
-        <td>{{ entry_what(item) }}</td>
+        <td>{{ entry_what(item, back) }}</td>
         <td>{{ entry_where(e) }}</td>
         <td class="nowrap">{{ e.actor }}</td>
         <td class="nowrap"><span class="chip">{{ item.area_label }}</span></td>

steward/templates/timeline/change_form.html

@@ -0,0 +1,83 @@
+{# timeline/change_form.html — record a change by hand, or edit one (timeline.changes):
+   what was done, the area it is about, the hosts, when, and any detail. Saving
+   returns to `back`, the page the form was opened from. #}
+{% extends "base.html" %}
+{% from "_macros.html" import crumbs, page_header %}
+{% set title = "Edit a recorded change" if entry else "Record a change" %}
+{% block title %}{{ title }} — Timeline — Steward{% endblock %}
+{% block breadcrumb %}{{ crumbs([("Timeline", "/timeline/"), (title, "")]) }}{% endblock %}
+{% block content %}
+{{ page_header(title, "Something Steward can't see happen: a config edited, a disk swapped, a service moved.") }}
+
+{% if error %}<div class="alert alert-error" role="alert">{{ error }}</div>{% endif %}
+
+<form method="post" action="{{ '/timeline/changes/' ~ entry.id if entry else '/timeline/changes' }}" class="form-page">{{ csrf_field() }}
+  <input type="hidden" name="back" value="{{ back }}">
+  <section class="card form-section" aria-labelledby="chg-what">
+    <h2 id="chg-what" class="section-title">The change</h2>
+    <div class="field">
+      <label class="field-label" for="chg-summary">What was done</label>
+      <input class="input" id="chg-summary" type="text" name="summary" value="{{ values.summary }}"
+             maxlength="300" required autofocus placeholder="e.g. Moved Postgres data to the new SSD">
+    </div>
+    <div class="field">
+      <label class="field-label" for="chg-area">Area</label>
+      <select class="input" id="chg-area" name="area" required>
+        <option value="">— pick one —</option>
+        {% for key, label in areas %}<option value="{{ key }}"{% if values.area == key %} selected{% endif %}>{{ label }}</option>{% endfor %}
+      </select>
+      <span class="field-hint">What part of the infrastructure it is about.</span>
+    </div>
+    <div class="field">
+      <label class="field-label" for="chg-at">When ({{ tz_label() }})</label>
+      <input class="input" id="chg-at" type="datetime-local" name="at" value="{{ values.at }}" required>
+    </div>
+    <div class="field">
+      <label class="field-label" for="chg-subject">What it was done to <span class="tone-dim">(optional)</span></label>
+      <input class="input" id="chg-subject" type="text" name="subject" value="{{ values.subject }}"
+             maxlength="255" placeholder="e.g. postgres, the core switch, /etc/fstab">
+    </div>
+    <div class="field">
+      <label class="field-label" for="chg-note">Detail <span class="tone-dim">(optional)</span></label>
+      <textarea class="input" id="chg-note" name="note" rows="4" maxlength="4000"
+                placeholder="Why, how, and anything to know if it goes wrong.">{{ values.note }}</textarea>
+    </div>
+  </section>
+
+  <section class="card form-section" aria-labelledby="chg-hosts">
+    <h2 id="chg-hosts" class="section-title">Hosts</h2>
+    <p class="field-hint">The change shows in each ticked host's history. Tick none for a change not on any one host.</p>
+    {% if hosts %}
+    <div class="check-list">
+      {% for h in hosts %}
+      <label class="field-check">
+        <input type="checkbox" name="hosts" value="{{ h }}"{% if h in values.hosts %} checked{% endif %}>
+        <span>{{ h }}</span>
+      </label>
+      {% endfor %}
+    </div>
+    {% else %}
+    <p class="tone-muted">No hosts yet.</p>
+    {% endif %}
+  </section>
+
+  <div class="form-actions">
+    <button type="submit" class="btn">{{ "Save" if entry else "Record the change" }}</button>
+    <a href="{{ back }}" class="btn btn-ghost">Cancel</a>
+  </div>
+</form>
+
+{% if entry %}
+<section class="card danger-zone" aria-labelledby="chg-delete">
+  <div>
+    <h2 id="chg-delete" class="section-title">Delete this change</h2>
+    <p class="field-hint">Recorded by {{ entry.actor }}. Deleting takes it off the timeline; the audit log keeps that it was.</p>
+  </div>
+  <form method="post" action="/timeline/changes/{{ entry.id }}/delete"
+        data-confirm="Delete “{{ entry.summary }}” from the timeline?">{{ csrf_field() }}
+    <input type="hidden" name="back" value="{{ back }}">
+    <button class="btn btn-danger" type="submit">Delete</button>
+  </form>
+</section>
+{% endif %}
+{% endblock %}

steward/templates/timeline/list.html

@@ -8,6 +8,7 @@
 {% block title %}Timeline — Steward{% endblock %}
 {% block content %}
 {% call page_header("Timeline", "What happened, newest first: alerts, playbook runs and changes, on every host.") %}
+  {% if session.user_role in ('operator', 'admin') %}<a class="btn btn-sm" href="/timeline/changes/new?{{ ({'host': filters.host, 'back': back} if filters.host else {'back': back})|urlencode }}">Record a change</a>{% endif %}
   {% if session.user_role == 'admin' %}<a class="btn btn-ghost btn-sm" href="/settings/timeline/">Areas and types</a>{% endif %}
 {% endcall %}