feat(tasks): refresh button in cron panel + auto-refresh on job creation (closes #835)

* feat(tasks): refresh button in cron panel + hermes:cron_created event

Add a ↺ refresh button to the Scheduled Jobs header so the job list can
be reloaded without a full page refresh. Closes #835.

- static/index.html: ↺ button with cronRefreshBtn id, calls loadCrons(true)
- static/panels.js: loadCrons(animate) dims+disables the button while fetching,
  restores it in finally; hermes:cron_created window event auto-refreshes list
  when the agent creates a job from chat

* test: add regression tests for cron refresh button + event listener

The PR shipped without automated coverage (pure UI wiring).  Filling that
gap with 8 source-level tests:

- Refresh button element exists with aria-label + title (icon-only a11y)
- Button wires onclick to loadCrons(true) for the dim animation
- Button sits in the same header row as "New job"
- loadCrons() now accepts an animate parameter
- loadCrons() restores the button's opacity/disabled in finally (so a
  throwing fetch doesn't leave the button stuck)
- hermes:cron_created window listener is registered at module scope
- Listener calls loadCrons() when dispatched

Also rebased onto master (CHANGELOG conflict resolved — v0.50.143 →
v0.50.142 since master's top is currently v0.50.141).

Full suite: 1750 passed, 0 new failures.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: nesquena-hermes <nesquena-hermes@users.noreply.github.com>
Co-authored-by: Nathan Esquenazi <nesquena@gmail.com>
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

static/index.html

@@ -48,7 +48,10 @@
     <div class="panel-view" id="panelTasks">
       <div class="sidebar-section" style="padding-bottom:4px;display:flex;align-items:center;justify-content:space-between">
         <div style="font-size:11px;color:var(--muted)" data-i18n="scheduled_jobs">Scheduled jobs</div>
-        <button class="cron-btn run" style="padding:3px 8px;font-size:10px" onclick="toggleCronForm()">+ <span data-i18n="new_job">New job</span></button>
+        <div style="display:flex;gap:4px;align-items:center">
+          <button class="cron-btn" id="cronRefreshBtn" style="padding:3px 7px;font-size:10px;line-height:1" onclick="loadCrons(true)" title="Refresh job list" aria-label="Refresh job list"><svg width="11" height="11" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.5" stroke-linecap="round" stroke-linejoin="round" aria-hidden="true"><polyline points="23 4 23 10 17 10"/><path d="M20.49 15a9 9 0 1 1-2.12-9.36L23 10"/></svg></button>
+          <button class="cron-btn run" style="padding:3px 8px;font-size:10px" onclick="toggleCronForm()">+ <span data-i18n="new_job">New job</span></button>
+        </div>
       </div>
       <!-- Create job form (hidden by default) -->
       <div id="cronCreateForm" style="display:none;padding:8px 12px;border-bottom:1px solid var(--border);flex-shrink:0">