feat(mana): migrate subscription page to workbench app

Extract /mana route into lib/modules/mana/ListView.svelte. Register as
workbench app id='mana' with Crown icon (amber). The page shows the
SubscriptionPage component from @mana/subscriptions.

- Delete routes/(app)/mana/+page.svelte
- Update PillNavigation manaHref to /?app=mana

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/mana/apps/web/src/lib/app-registry/apps.ts

@@ -71,6 +71,7 @@ import {
 	SquaresFour,
 	Scroll,
 	Spiral,
+	Crown,
 } from '@mana/shared-icons';
 
 // ── Apps with entity capabilities ───────────────────────────
@@ -1087,6 +1088,16 @@ registerApp({
 	},
 });
 
+registerApp({
+	id: 'mana',
+	name: 'Mana',
+	color: '#F59E0B',
+	icon: Crown,
+	views: {
+		list: { load: () => import('$lib/modules/mana/ListView.svelte') },
+	},
+});
+
 registerApp({
 	id: 'spiral',
 	name: 'Mana Spiral',

apps/mana/apps/web/src/lib/modules/mana/ListView.svelte

@@ -1,3 +1,7 @@
+<!--
+  Mana — Workbench-embedded subscription / pricing page.
+  Shows available plans and one-time credit packages.
+-->
 <script lang="ts">
 	import { SubscriptionPage } from '@mana/subscriptions';
 
@@ -14,11 +18,6 @@
 	}
 </script>
 
-<svelte:head>
-	<title>Mana - Mana</title>
-</svelte:head>
-
-<!-- Toast notification -->
 {#if toastMessage}
 	<div
 		class="fixed bottom-6 left-1/2 z-50 -translate-x-1/2 rounded-lg bg-amber-600 px-5 py-3 text-sm font-medium text-white shadow-lg"
@@ -42,9 +41,10 @@
 
 <style>
 	.mana-page {
-		min-height: 100%;
+		height: 100%;
 		width: 100%;
+		overflow-y: auto;
 		overflow-x: hidden;
-		background-color: hsl(var(--color-background));
+		padding: 0.75rem;
 	}
 </style>

apps/mana/apps/web/src/routes/(app)/+layout.svelte

@@ -974,7 +974,7 @@
 					currentSyncLabel={syncStatus.label}
 					{appItems}
 					{userEmail}
-					manaHref="/mana"
+					manaHref="/?app=mana"
 					profileHref="/?app=profile"
 					spiralHref="/?app=spiral"
 					creditsHref="/credits"