feat: use PHP 8.5 instead of 8.3 in workflows

- Install PHP 8.5 via sury.org repository
- Matches composer.json requirement (^8.5)
- Consistent with Dockerfiles using php:8.5.0RC3-fpm
- No longer need --ignore-platform-reqs flag
- RC3 is stable enough and aligns with production setup

.gitea/workflows/production-deploy.yml

@@ -89,7 +89,7 @@ jobs:
       - name: Install dependencies
         run: |
           cd /workspace/repo
-          composer install --no-interaction --prefer-dist --optimize-autoloader --ignore-platform-reqs
+          composer install --no-interaction --prefer-dist --optimize-autoloader
 
       - name: Save Composer cache
         run: |

.gitea/workflows/security-scan.yml

@@ -90,7 +90,7 @@ jobs:
       - name: Install dependencies
         run: |
           cd /workspace/repo
-          composer install --prefer-dist --no-progress --no-dev --ignore-platform-reqs
+          composer install --prefer-dist --no-progress --no-dev
 
       - name: Save Composer cache
         run: |