Refactoring and cleanup

* Moved logic from entrypoint to a dedicated class.
* Disabled automatic flush of state.
* Added locking support to prevent multiple instances.
* Added logging
* Added base interface for CredentialsLoader

src/State/Lockfile.php

@@ -0,0 +1,36 @@
+<?php
+
+namespace NoccyLabs\FreshDocker\State;
+
+class Lockfile
+{
+    private string $filename;
+
+    private int $maxLock = 3600;
+
+    public function __construct(string $filename)
+    {
+        $this->filename = $filename;
+        register_shutdown_function([$this,"release"]);
+    }
+
+    public function lock()
+    {
+        if (file_exists($this->filename)) {
+            if (time() - filemtime($this->filename) < $this-$maxLock) {
+                throw new \RuntimeException("Lockfile {$this->filename} already exists");
+            }
+        }
+        touch($this->filename);
+    }
+
+    public function release()
+    {
+        if (file_exists($this->filename)) {
+            unlink($this->filename);
+        }
+
+    }
+
+
+}