Initial commit: Runware-powered content generator foundation

Laravel app with a cost-tracked Runware.ai integration (image, video,
text generation), a hard monthly EUR budget cap with live USD/EUR FX
conversion, and a locally-maintained model/pricing table since
Runware's model-search API doesn't expose pricing.

app/Services/Runware/CostEstimator.php

@@ -0,0 +1,27 @@
+<?php
+
+namespace App\Services\Runware;
+
+use App\Models\RunwareModel;
+
+/**
+ * Pre-flight cost estimation used by BudgetGuard before a Runware call is
+ * made. Deliberately conservative — the real cost is always reconciled
+ * afterward from Runware's response `cost` field (or, for text, `usage.cost`).
+ */
+class CostEstimator
+{
+    protected const DEFAULT_VIDEO_DURATION_SECONDS = 5;
+
+    protected const DEFAULT_TEXT_TOKEN_BUDGET = 2048;
+
+    public function estimateUsd(RunwareModel $model, array $params): float
+    {
+        return match ($model->unit) {
+            'per_image' => (float) $model->price_usd * (int) ($params['numberResults'] ?? 1),
+            'per_second' => (float) $model->price_usd * (int) ($params['duration'] ?? self::DEFAULT_VIDEO_DURATION_SECONDS),
+            'per_million_tokens' => (float) $model->price_usd
+                * (((int) ($params['max_completion_tokens'] ?? self::DEFAULT_TEXT_TOKEN_BUDGET)) / 1_000_000),
+        };
+    }
+}