feat(shared-auth-ui): add GuestRegistrationNudge + complete feature texts + improve seed data

- Add GuestRegistrationNudge component: shows a floating banner after
  X minutes of guest usage to encourage sign-up (bottom-center, dismissible)
- Add guestNudge.ts utilities (session tracking, delay, dismiss via localStorage)
- Add feature texts for all 16 missing apps in GuestWelcomeModal
- Integrate nudge in Todo app as reference implementation (3min delay)
- Improve SkillTree seed: 3 skills across branches, 6 activities, 1 achievement
- Improve Zitare seed: 5 favorites, 2 themed lists instead of 1

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

apps/skilltree/apps/web/src/lib/data/guest-seed.ts

@@ -1,32 +1,45 @@
 /**
  * Guest seed data for the SkilltTree app.
  *
- * Provides a demo skill with an activity to showcase the leveling system.
+ * Provides demo skills across multiple branches with activities and an achievement
+ * to showcase the leveling system, XP progression, and activity feed.
  */
 
-import type { LocalSkill, LocalActivity } from './local-store';
+import type { LocalSkill, LocalActivity, LocalAchievement } from './local-store';
 
-const DEMO_SKILL_ID = 'demo-coding';
+const DEMO_CODING_ID = 'demo-coding';
+const DEMO_FITNESS_ID = 'demo-fitness';
+const DEMO_CREATIVE_ID = 'demo-creative';
 
 export const guestSkills: LocalSkill[] = [
 	{
-		id: DEMO_SKILL_ID,
+		id: DEMO_CODING_ID,
 		name: 'Programmieren',
 		description: 'Software-Entwicklung und Coding-Skills',
 		branch: 'intellect',
 		icon: '💻',
-		currentXp: 150,
-		totalXp: 150,
+		currentXp: 250,
+		totalXp: 250,
 		level: 1,
 	},
 	{
-		id: 'demo-fitness',
+		id: DEMO_FITNESS_ID,
 		name: 'Fitness',
 		description: 'Körperliche Fitness und Training',
 		branch: 'body',
 		icon: '💪',
-		currentXp: 50,
-		totalXp: 50,
+		currentXp: 120,
+		totalXp: 120,
+		level: 1,
+	},
+	{
+		id: DEMO_CREATIVE_ID,
+		name: 'Zeichnen',
+		description: 'Illustration, Skizzen und visuelles Denken',
+		branch: 'creativity',
+		icon: '🎨',
+		currentXp: 60,
+		totalXp: 60,
 		level: 0,
 	},
 ];
@@ -34,18 +47,61 @@ export const guestSkills: LocalSkill[] = [
 export const guestActivities: LocalActivity[] = [
 	{
 		id: 'activity-1',
-		skillId: DEMO_SKILL_ID,
+		skillId: DEMO_CODING_ID,
 		xpEarned: 100,
 		description: 'TypeScript-Projekt aufgesetzt',
 		duration: 60,
-		timestamp: new Date(Date.now() - 2 * 24 * 60 * 60 * 1000).toISOString(),
+		timestamp: new Date(Date.now() - 4 * 24 * 60 * 60 * 1000).toISOString(),
 	},
 	{
 		id: 'activity-2',
-		skillId: DEMO_SKILL_ID,
+		skillId: DEMO_FITNESS_ID,
+		xpEarned: 50,
+		description: '5 km Joggen im Park',
+		duration: 35,
+		timestamp: new Date(Date.now() - 3 * 24 * 60 * 60 * 1000).toISOString(),
+	},
+	{
+		id: 'activity-3',
+		skillId: DEMO_CODING_ID,
+		xpEarned: 100,
+		description: 'REST API mit Hono gebaut',
+		duration: 90,
+		timestamp: new Date(Date.now() - 2 * 24 * 60 * 60 * 1000).toISOString(),
+	},
+	{
+		id: 'activity-4',
+		skillId: DEMO_CREATIVE_ID,
+		xpEarned: 60,
+		description: 'Erste Skizzen mit Procreate',
+		duration: 45,
+		timestamp: new Date(Date.now() - 2 * 24 * 60 * 60 * 1000).toISOString(),
+	},
+	{
+		id: 'activity-5',
+		skillId: DEMO_FITNESS_ID,
+		xpEarned: 70,
+		description: 'Krafttraining — Oberkörper',
+		duration: 50,
+		timestamp: new Date(Date.now() - 1 * 24 * 60 * 60 * 1000).toISOString(),
+	},
+	{
+		id: 'activity-6',
+		skillId: DEMO_CODING_ID,
 		xpEarned: 50,
 		description: 'Unit Tests geschrieben',
 		duration: 30,
-		timestamp: new Date(Date.now() - 1 * 24 * 60 * 60 * 1000).toISOString(),
+		timestamp: new Date(Date.now() - 12 * 60 * 60 * 1000).toISOString(),
+	},
+];
+
+export const guestAchievements: LocalAchievement[] = [
+	{
+		id: 'achievement-1',
+		key: 'first-skill',
+		name: 'Erste Schritte',
+		description: 'Deinen ersten Skill erstellt',
+		icon: '🌱',
+		unlockedAt: new Date(Date.now() - 4 * 24 * 60 * 60 * 1000).toISOString(),
 	},
 ];

apps/skilltree/apps/web/src/lib/data/local-store.ts

@@ -6,7 +6,7 @@
  */
 
 import { createLocalStore, type BaseRecord } from '@manacore/local-store';
-import { guestSkills, guestActivities } from './guest-seed';
+import { guestSkills, guestActivities, guestAchievements } from './guest-seed';
 
 // ─── Types ──────────────────────────────────────────────────
 
@@ -58,6 +58,7 @@ export const skilltreeStore = createLocalStore({
 		{
 			name: 'achievements',
 			indexes: ['key', 'unlockedAt'],
+			guestSeed: guestAchievements,
 		},
 	],
 	sync: {