fix: resolve autoload when running as phar

agent/box.json

@@ -1,6 +1,6 @@
 {
     "main": "src/sentry-agent.php",
     "output": "../bin/sentry-agent",
-    "alias": "sentry-agent.phar",
+    "alias": "sentry-agent",
     "timestamp": "20250904"
 }

agent/src/sentry-agent.php

@@ -15,7 +15,15 @@
     exit;
 }
 
-require $_composer_autoload_path ?? __DIR__ . '/../vendor/autoload.php';
+if (class_exists('Phar') && Phar::running(false) !== '') {
+    // If running the .phar directly from ./vendor/bin/, we don't want to use $_composer_autoload_path since this
+    // will load the projects files and lead to ClassNotFound errors.
+    // We want to use the autoload.php from the phar itself.
+    require __DIR__ . '/../vendor/autoload.php';
+} else {
+    // This works fine for local development or if running the phar from ./vendor/sentry/sentry-agent/bin/
+    require $_composer_autoload_path ?? __DIR__ . '/../vendor/autoload.php';
+}
 
 // @TODO: "sentryagent" with a 5 in front, it's a unused "user port": https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml?search=5148
 //        Maybe there is a better way to select a port to use but for now this is fine.

bin/sentry-agent.sig

@@ -1 +1 @@
-52CA959C330A3E693A9977E17A16D8244AE7ECE1D807F8470D26FBB370A34F71E04731127DDBBC0EB5C73091023B20EB4A73754170322FF81EB037898AF5F667
+08702101B575BBFB940A721633C715043D2230509868C02E738B28971A3700182F914BDA9A8AC9AC43BB3944E64DDEE50BD13499FB97082966B860BDBFCA9F18