hermes - 💡(How to fix) Fix Update Now can show success/restart without applying any update when no targets are selected

Bug description

The WebUI Update Now button can show Update applied — restarting… and enter the restart/reload wait flow even when it sends zero /api/updates/apply requests.

This makes it look like the update succeeded, but no git pull is actually attempted.

Root cause

In /app/static/ui.js, applyUpdates() builds its target list from window._updateData:

const targets=[];
if(window._updateData?.webui?.behind>0) targets.push('webui');
if(window._updateData?.agent?.behind>0) targets.push('agent');

But if targets is empty, execution still falls through to:

showToast('Update applied — restarting…');
sessionStorage.removeItem('hermes-update-checked');
sessionStorage.removeItem('hermes-update-dismissed');
_waitForServerThenReload();

So stale/missing update data, a cache race, or any case where the banner/button remains visible while window._updateData has no behind > 0 targets can produce a false-success update.

Expected behavior

If no update targets are selected, the UI should not claim success or start the restart wait flow. It should show an actionable error and reset the button.

Example guard:

if(!targets.length){
  const msg='No update target selected. Refresh update status and retry.';
  if(errEl){errEl.textContent=msg;errEl.style.display='block';}
  else showToast(msg,5000,'error');
  resetApplyButton(0);
  return;
}

Actual behavior

The UI can show:

Update applied — restarting…

without sending any apply request or running any git command.

Why this matters

This is confusing for self-update troubleshooting. It makes browser cache/proxy/reload behavior look like a git/update failure, when the backend may never have been called.

Observed during troubleshooting:

• manual git pull --ff-only origin main worked as UID 1000
• repo permissions were correct
• backend apply_update("agent") worked when invoked directly
• git reflog showed no HEAD movement from the WebUI button attempt
• frontend code allowed a zero-target false success

Environment

• Hermes WebUI version: v0.51.130
• Agent checkout path: /home/hermes/.hermes/hermes-agent
• WebUI process UID/GID: 1000:1000
• Static JS is served with long immutable cache headers, which can make the false-success state harder to distinguish from browser/proxy cache issues.

Suggested fix

Add an early guard in applyUpdates() after target selection so the function returns before displaying success/restart if targets.length === 0.

Optional follow-up: add lightweight backend logging around /api/updates/apply so failed/blocked update attempts are visible in logs.