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/Log.php

@@ -0,0 +1,39 @@
+<?php
+
+namespace NoccyLabs\FreshDocker\State;
+
+class Log
+{
+    private bool $verbose = false;
+
+    private array $log = [];
+
+    public function __construct(bool $verbose=false)
+    {
+        $this->verbose = $verbose;
+    }
+
+    public function setVerbose(bool $verbose)
+    {
+        $this->verbose = $verbose;
+    }
+
+    public function append(string $message)
+    {
+        array_push($this->log, $message);
+        if ($this->verbose) {
+            fwrite(STDOUT, $message . "\n");
+        }
+    }
+
+    public function flush()
+    {
+        if ($this->verbose) return;
+        fwrite(STDOUT, join("\n", $this->log)."\n");
+    }
+
+    public function asString(): string
+    {
+        return join("\n", $this->log);
+    }
+}