Fix CI/CD job dependencies and YAML syntax

- Make deploy job dependency optional in ghost-upload jobs
- Change preview job to depend on staging instead of deploy
- Ensures pipeline works on feature branches without deploy job

.gitlab-ci.yml

@@ -39,7 +39,7 @@ preview:
     - echo "Deploying branch preview..."
     - echo "Preview available at preview URL"
   needs:
-    - deploy
+    - staging
   artifacts:
     paths:
       - public

ghost-upload/.gitlab-ci.yml

@@ -10,7 +10,9 @@ publish:
     - cd ./ghost-upload
     - cargo run
   needs:
-    - deploy
+    - job: deploy
+      optional: true
+    - staging
 
 # Manual trigger to force update all Ghost posts
 force-update-ghost:
@@ -21,13 +23,11 @@ force-update-ghost:
     - cd ./ghost-upload
     - FORCE_UPDATE=true cargo run
   needs:
-    - deploy
+    - job: deploy
+      optional: true
+    - staging
   rules:
     - when: manual
       allow_failure: false
-  # rules:
-  #   - if: "$CI_COMMIT_BRANCH == $CI_DEFAULT_BRANCH"
-  #     when: manual
-  #     allow_failure: false
   variables:
     FORCE_UPDATE: "true"