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/routes/triggers/[id]/+page.svelte

@@ -1,5 +1,5 @@
 <script lang="ts">
-	import { onDestroy, onMount } from 'svelte';
+	import { onDestroy } from 'svelte';
 	import { goto } from '$app/navigation';
 	import { page } from '$app/stores';
 	import * as api from '$lib/api';
@@ -257,7 +257,13 @@
 		return v === key ? k : v;
 	}
 
-	onMount(load);
+	// SvelteKit reuses this component instance across /triggers/A → /triggers/B,
+	// so onMount(load) would only fire once. The id-keyed effect reloads on
+	// param change.
+	$effect(() => {
+		const _ = id;
+		load();
+	});
 </script>
 
 <svelte:head>