fix: require system-metrics ^1.2 for ProcessStats::delta property

CI fails with --prefer-lowest because it installs system-metrics v1.0.0
which lacks the $delta property in ProcessStats. The delta property
was added in v1.1.0.

Updated constraint from ^1.0 to ^1.2 to ensure CI gets a compatible
version even with --prefer-lowest.

Fixes ProcessMetricsIntegrationTest and ChildProcessTrackingTest
failures in CI.

Author: sylvesterdamgaard

composer.json

@@ -22,7 +22,7 @@
     ],
     "require": {
         "php": "^8.3|^8.4",
-        "gophpeek/system-metrics": "^1.0",
+        "gophpeek/system-metrics": "^1.2",
         "illuminate/contracts": "^11.0|^12.0",
         "spatie/laravel-package-tools": "^1.16",
         "spatie/laravel-prometheus": "^1.3"