Feature: Implement multi-stage Conversation Flow Engine with TestFlow

backend/app/Core/Flows/FlowResult.php

@@ -0,0 +1,55 @@
+<?php
+
+namespace App\Core\Flows;
+
+/**
+ * FlowResult
+ * Holds response details after handling a single step in a conversation flow.
+ */
+class FlowResult
+{
+    private string $replyText;
+    private string $nextStep;
+    private bool $finished;
+    private ?string $mediaUrl;
+
+    public function __construct(string $replyText, string $nextStep, bool $finished = false, ?string $mediaUrl = null)
+    {
+        $this->replyText = $replyText;
+        $this->nextStep = $nextStep;
+        $this->finished = $finished;
+        $this->mediaUrl = $mediaUrl;
+    }
+
+    /**
+     * Get the reply message text to send to the contact
+     */
+    public function getReplyText(): string
+    {
+        return $this->replyText;
+    }
+
+    /**
+     * Get the next step key
+     */
+    public function getNextStep(): string
+    {
+        return $this->nextStep;
+    }
+
+    /**
+     * Check if the flow is finished (to be destroyed)
+     */
+    public function isFinished(): bool
+    {
+        return $this->finished;
+    }
+
+    /**
+     * Get target media URL (if any)
+     */
+    public function getMediaUrl(): ?string
+    {
+        return $this->mediaUrl;
+    }
+}