Alerts tab, Docker tab, nine new skins including HUD, a colour for every machine

Alerts: rules over sensors, watched fleet-wide from the hub; ntfy and webhook channels;
firing count on the rail. Docker: containers by stack with live use, start/stop/restart,
following logs, inspect, images/volumes/networks. Skins: HUD, Nord, Gruvbox, Catppuccin
(+Latte), Dracula, Tokyo Night, Solarized (+Light). Accents: per-machine colour.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

web/src/App.tsx

@@ -5,6 +5,7 @@ import Shell from './Shell'
 import { Dialogs } from './ui'
 import { applyTheme, currentThemeId } from './themes'
 import { getRefreshMs, setRefreshMs } from './prefs'
+import { setAccents } from './accents'
 
 export default function App() {
   const [me, setMe] = useState<Me | null | undefined>(undefined)
@@ -15,6 +16,7 @@ export default function App() {
       api.uiPrefs().then((p) => {
         if (p.theme && p.theme !== currentThemeId()) applyTheme(p.theme)
         if (p.refreshMs && p.refreshMs !== getRefreshMs()) setRefreshMs(p.refreshMs)
+        if (p.accents && typeof p.accents === 'object') setAccents(p.accents, false)
       }).catch(() => { /* keep local */ })
     } catch (e) { if (e instanceof Unauthenticated) setMe(null) }
   }, [])