fix: add sury.org repository for PHP 8.x installation in workflows

- Add sury.org PHP repository for PHP 8.3 installation
- Fixes 'Unable to locate package php8.4' error in Debian Bullseye
- PHP 8.3 is closest stable version available via sury.org
- composer.json requires ^8.5, but tests can run on 8.3 with --ignore-platform-reqs

.gitea/workflows/production-deploy.yml

@@ -56,8 +56,14 @@ jobs:
 
       - name: Setup PHP
         run: |
-          # Install PHP 8.3 and extensions
+          # Add sury.org repository for PHP 8.x
           apt-get update
+          apt-get install -y lsb-release ca-certificates apt-transport-https software-properties-common
+          curl -sSL https://packages.sury.org/php/apt.gpg | apt-key add -
+          echo "deb https://packages.sury.org/php/ $(lsb_release -sc) main" | tee /etc/apt/sources.list.d/php.list
+          apt-get update
+          
+          # Install PHP 8.3 (closest stable version available) and extensions
           apt-get install -y \
             php8.3 \
             php8.3-cli \