feat: fatura PDF, hizmet/yazılım atama dosya ekleri

- /print/invoices/[id] sayfası: A4 fatura yazdırma/PDF (AutoPrint + PrintActionBar)
- Fatura detayı header'ına PDF butonu eklendi (Yazdır yerine)
- Appwrite Storage: entity-attachments bucket (20MB, şifreli)
- Appwrite Tables: attachments collection (tenantId, entityType, entityId, fileId, name, size, mimeType)
- attachment-actions.ts: fetchAttachmentsAction, uploadAttachmentAction, deleteAttachmentAction
- AttachmentsPanel bileşeni: dosya yükleme/listeleme/silme, edit modunda görünür
- Hizmet ve yazılım atama form sheet'lerine AttachmentsPanel entegrasyonu
- /api/files/[attachmentId]: güvenli proxy indirme (tenant doğrulama + admin key ile Appwrite'a istek)

src/app/(dashboard)/invoices/[id]/components/header-actions.tsx

@@ -2,7 +2,7 @@
 
 import { useState, useTransition } from "react";
 import { useRouter } from "next/navigation";
-import { Loader2, Pencil, Printer, Trash2 } from "lucide-react";
+import { FileDown, Loader2, Pencil, Trash2 } from "lucide-react";
 import { toast } from "sonner";
 
 import { Button } from "@/components/ui/button";
@@ -45,9 +45,13 @@ export function InvoiceHeaderActions({ invoice, customers }: Props) {
   return (
     <>
       <div className="flex flex-wrap gap-2">
-        <Button variant="outline" size="sm" onClick={() => window.print()}>
-          <Printer className="size-3.5" />
-          Yazdır
+        <Button
+          variant="outline"
+          size="sm"
+          onClick={() => window.open(`/print/invoices/${invoice.id}`, "_blank")}
+        >
+          <FileDown className="size-3.5" />
+          PDF
         </Button>
         <Button variant="outline" size="sm" onClick={() => setEditOpen(true)}>
           <Pencil className="size-3.5" />