feat: setup Supabase Storage bucket for restaurant assets and add mobile upload helper

apps/mobile/src/lib/storage.ts

@@ -0,0 +1,36 @@
+import { supabase } from "./supabase";
+
+export const BUCKET_NAME = "restaurant-assets";
+
+export type AssetFolder = "logos" | "covers" | "items";
+
+/**
+ * Uploads an image file (logo, cover banner, item photo) to Supabase Storage
+ * and returns the public CDN URL.
+ */
+export async function uploadImageToSupabase(
+  fileUri: string,
+  folder: AssetFolder = "items"
+): Promise<string> {
+  const response = await fetch(fileUri);
+  const blob = await response.blob();
+  const fileExt = fileUri.split(".").pop()?.toLowerCase() || "jpg";
+  const fileName = `${folder}/${Date.now()}-${Math.random().toString(36).substring(2, 9)}.${fileExt}`;
+
+  const { data, error } = await supabase.storage
+    .from(BUCKET_NAME)
+    .upload(fileName, blob, {
+      contentType: `image/${fileExt === "png" ? "png" : "jpeg"}`,
+      upsert: true,
+    });
+
+  if (error) {
+    throw new Error(`Resim yükleme hatası: ${error.message}`);
+  }
+
+  const { data: publicUrlData } = supabase.storage
+    .from(BUCKET_NAME)
+    .getPublicUrl(data.path);
+
+  return publicUrlData.publicUrl;
+}