feat: portfolio redesign with i18n, RBC project showcase, CI/CD

- Add i18n support (EN/ZH) with language toggle
- Redesign header with education dropdown, contact copy buttons
- Add RBC project showcase with bullet points, skills highlighting
- Create terraform-drift placeholder page
- Add ProjectShowcase component with media toggle (image/video)
- Update experience timeline with action-driven descriptions
- Add Docker + Forgejo CI workflow for image builds
- Update K8s manifests for riotpiao.com ingress
- Add DESIGN.md documenting design system patterns

infra/homarr/base/ingress.yaml

@@ -9,10 +9,10 @@ spec:
   ingressClassName: nginx
   tls:
   - hosts:
-    - homarr.riotpiao.homelab.com
+    - homarr.riotpiao.com
     secretName: homarr-tls
   rules:
-  - host: homarr.riotpiao.homelab.com
+  - host: homarr.riotpiao.com
     http:
       paths:
       - path: /