test(unit): Add Neuron and Validator regression tests

tests/Unit/NeuronTest.php

@@ -0,0 +1,59 @@
+<?php
+
+namespace Tests\Unit;
+
+use Libs\Neuron;
+use Tests\TestCase;
+
+/**
+ * NeuronTest - DuckBrain test harness
+ *
+ * Regression net para el contenedor de valores del core: construcción
+ * desde array/objeto, propiedades dinámicas y null en inexistentes.
+ */
+final class NeuronTest extends TestCase
+{
+    public function testConstructFromAssociativeArray(): void
+    {
+        $n = new Neuron(['username' => 'kj', 'level' => 3]);
+
+        $this->assertSame('kj', $n->username);
+        $this->assertSame(3, $n->level);
+    }
+
+    public function testConstructFromObjectCopiesPublicProperties(): void
+    {
+        $source = new \stdClass();
+        $source->id = 7;
+        $source->email = 'kj@example.com';
+
+        $n = new Neuron($source);
+
+        $this->assertSame(7, $n->id);
+        $this->assertSame('kj@example.com', $n->email);
+    }
+
+    public function testUndefinedPropertyIsNullWithoutNotice(): void
+    {
+        $n = new Neuron();
+
+        $this->assertNull($n->thisDoesNotExist);
+    }
+
+    public function testDynamicPropertiesCanBeAssignedAndRead(): void
+    {
+        $n = new Neuron();
+        $n->fresh = ['a', 'b'];
+
+        $this->assertSame(['a', 'b'], $n->fresh);
+    }
+
+    public function testNestedValuesArePreservedVerbatim(): void
+    {
+        $payload = ['meta' => ['tags' => ['x', 'y'], 'n' => null]];
+        $n = new Neuron($payload);
+
+        $this->assertSame($payload['meta'], $n->meta);
+        $this->assertNull($n->meta['n']);
+    }
+}