Migrate from Vite to Next.js 15 with SSR

- Replace Vite + React Router with Next.js 15 App Router
- Implement i18n with next-intl (URL-based: /de, /en, /sr)
- Add SSR/SSG for all pages (48 static pages generated)
- Setup Supabase SSR client for auth
- Migrate all pages: Home, About, Portfolio, Blog, Contact, Login, Dashboard, Imprint, Privacy, Terms
- Add Docker support with standalone output
- Replace i18next with next-intl JSON translations
- Use next/image for optimized images

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

src/i18n/locales-old/en/pages/about/skills.ts

@@ -0,0 +1,46 @@
+// en/pages/about/skills.ts
+export const skills = {
+    title: 'Skills',
+    skillGroups: [
+        {
+            category: 'Development',
+            items: [
+                { name: 'Python', level: 90 },
+                { name: 'Google Ads', level: 85 },
+                { name: 'Meta Ads', level: 85 }
+            ]
+        },
+        {
+            category: 'E-Commerce',
+            items: [
+                { name: 'Shopware', level: 85 },
+                { name: 'Shopify', level: 85 },
+                { name: 'WooCommerce', level: 85 }
+            ]
+        },
+        {
+            category: 'System Administration',
+            items: [
+                { name: 'JTL WAWI', level: 85 },
+                { name: 'Server', level: 75 },
+                { name: 'AirFlow', level: 60 }
+            ]
+        }
+    ],
+    ui: {
+        percentage: 'percent',
+        levelLabel: 'Level',
+        skillLevel: '{{level}}% proficiency in {{skill}}'
+    },
+    aria: {
+        skillGroup: 'Skill group for {{category}}',
+        skillBar: 'Progress bar for {{skill}}',
+        skillIcon: 'Icon for {{category}}',
+        selectSkill: 'Select skill'
+    },
+    screenReader: {
+        skillProgress: '{{skill}} with a level of {{level}} percent'
+    }
+} as const;
+
+export type SkillsTranslations = typeof skills;