Add public endpoints and refactor deployments

- Implemented public `/gallery/public` and `/events/public` endpoints for fetching published data without authentication.
- Updated persistent volume configuration for Fly.io across backend and static file serving.
- Adjusted frontend to dynamically fetch events and gallery images from backend API.
- Refined Woodpecker pipeline for clearer separation of backend and frontend deployments.

.woodpecker.yml

@@ -1,3 +1,9 @@
+when:
+  branch:
+    - main
+  event:
+    - push
+
 steps:
   deploy_frontend:
     image: node:20
@@ -9,7 +15,7 @@ steps:
       - export PATH="$HOME/.fly/bin:$PATH"
       - flyctl deploy --config fly.toml --app gallus-pub --remote-only
 
-  build_and_deploy_backend:
+  deploy_backend:
     image: node:20
     environment:
       FLY_API_TOKEN:
@@ -19,9 +25,3 @@ steps:
       - curl -L https://fly.io/install.sh | sh
       - export PATH="$HOME/.fly/bin:$PATH"
       - flyctl deploy --config fly.toml --app gallus-cms-backend --remote-only
-
-when:
-  branch:
-    - main
-  event:
-    - push