feat(apps): stepped creation wizard, branch previews, and app-creation fixes

This session (frontend focus):
- Rebuild /apps/new as a 4-step wizard (Basics → Configure → Trigger → Review):
  WizardRail, SourceKindPicker card grid, AppManifest review, per-step validation,
  ConfirmDialog-based unsaved-changes guard.
- Extract lib/workload/sourceForms.ts (single source of truth for source_config)
  + {Image,Compose,Static,Dockerfile}SourceForm + StaticDiscoveryWizard; fold the
  /apps/[id] edit form onto the same components (removes the duplication). Add
  vitest + sourceForms unit tests.
- Branch preview environments UI: /chain is_preview/preview_branch + a Preview
  environments panel on /apps/[id] (per-branch URLs, ConfirmDialog teardown, armed
  state); RegistryImagePicker on the registry trigger and the image source.
- Fixes: image-inspect 404 -> admin-gated POST /api/discovery/image/inspect;
  conflict-panel blur flicker; friendly localized discovery errors; CPU/Memory
  label hints; dashboard + /apps "Total workloads" count only source_kind workloads
  (drop stale trigger_kind gate); NPM cert/access-list name cache; EntityPicker
  empty-list guard.
- Update CLAUDE.md frontend conventions + add a Build & Test section.

Also captures pre-existing in-progress platform work (not from this session):
workload notifications, Prometheus metrics export, store lockfile, health probes,
backup hardening, and related store/webhook/scheduler changes.

web/src/lib/components/SystemDaemonsCard.svelte

@@ -210,7 +210,7 @@
 				</div>
 			{:else if !proxyConnected}
 				<div class="panel-error">
-					<code>{proxy.error ?? `${proxyProvider.toUpperCase()} is not reachable.`}</code>
+					<code>{proxy.error ?? $t('daemons.notReachable', { provider: proxyProvider.toUpperCase() })}</code>
 					<p>{$t('daemons.proxyHint')}</p>
 					{#if proxy.url}
 						<p class="url"><span class="kdim">URL</span> <code>{proxy.url}</code></p>