Summary

This PR adds two predefined server metadata environment variables for application deployments:

• COOLIFY_SERVER_NAME
• COOLIFY_SERVER_UUID

The injection is intentionally minimal and runtime-only, implemented in the existing ApplicationDeploymentJob::generate_coolify_env_variables() path.

Why

Issue #7738 asks for predefined server variables so an app can identify where it runs in multi-server deployments.

Behavior

• Adds COOLIFY_SERVER_NAME and COOLIFY_SERVER_UUID for runtime env generation.
• Keeps application-level precedence: if the app already defines either key, Coolify does not override it.
• Does not inject these variables for build-time env generation (keeps build cache behavior stable and avoids build-server/runtime-server mismatch).

Scope

• No schema changes
• No UI changes
• No API changes
• No server-level custom variable CRUD

Tests

Added tests/Unit/ApplicationDeploymentServerEnvVariablesTest.php with coverage for:

1. Runtime injection when keys are not overridden
2. No injection when app env already defines those keys
3. No injection in build-time env generation

Verification command used

docker run --rm -t --user root \
  -v /var/www/html:/var/www/html \
  -w /var/www/html docker.io/serversideup/php:8.4-fpm-nginx \
  sh -lc "install-php-extensions sockets >/tmp/install-sockets.log 2>&1 && php artisan test --compact tests/Unit/ApplicationDeploymentServerEnvVariablesTest.php"

/claim #7738