feat(skilltree): add central auth pages with shared components

- Add SkillTreeLogo to shared-branding (emerald green theme)
- Add login, register, forgot-password pages using shared-auth-ui
- Initialize authStore in layout alongside skillStore
- Add shared-auth-ui, shared-i18n, shared-branding dependencies
- German translations as default

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

packages/shared-branding/src/config.ts

@@ -233,6 +233,19 @@ export const APP_BRANDING: Record<AppId, AppBranding> = {
 		logoStroke: true,
 		logoStrokeWidth: 1.5,
 	},
+	skilltree: {
+		id: 'skilltree',
+		name: 'SkillTree',
+		tagline: 'Level Up Your Life',
+		primaryColor: '#10b981',
+		secondaryColor: '#34d399',
+		// Tree/branch icon representing skill progression
+		logoPath:
+			'M12 3v1.5M12 21v-1.5M12 9a3 3 0 100-6 3 3 0 000 6zm0 0v3m0 6a3 3 0 100-6 3 3 0 000 6zm-6-3h1.5m10.5 0h1.5M6 12a3 3 0 100-6 3 3 0 000 6zm0 0h3m6 0h3m-3 0a3 3 0 100-6 3 3 0 000 6z',
+		logoViewBox: '0 0 24 24',
+		logoStroke: true,
+		logoStrokeWidth: 1.5,
+	},
 };
 
 /**

packages/shared-branding/src/index.ts

@@ -32,6 +32,7 @@ export {
 	InventoryLogo,
 	ClockLogo,
 	QuestionsLogo,
+	SkillTreeLogo,
 } from './logos';
 
 // Configuration

packages/shared-branding/src/logos/SkillTreeLogo.svelte

@@ -0,0 +1,13 @@
+<script lang="ts">
+	import AppLogo from '../AppLogo.svelte';
+
+	interface Props {
+		size?: number;
+		color?: string;
+		class?: string;
+	}
+
+	let { size = 55, color, class: className = '' }: Props = $props();
+</script>
+
+<AppLogo app="skilltree" {size} {color} class={className} />

packages/shared-branding/src/logos/index.ts

@@ -19,3 +19,4 @@ export { default as MoodlitLogo } from './MoodlitLogo.svelte';
 export { default as InventoryLogo } from './InventoryLogo.svelte';
 export { default as ClockLogo } from './ClockLogo.svelte';
 export { default as QuestionsLogo } from './QuestionsLogo.svelte';
+export { default as SkillTreeLogo } from './SkillTreeLogo.svelte';

packages/shared-branding/src/types.ts

@@ -19,7 +19,8 @@ export type AppId =
 	| 'mail'
 	| 'moodlit'
 	| 'inventory'
-	| 'questions';
+	| 'questions'
+	| 'skilltree';
 
 /**
  * App branding configuration