Add chunked uploads and raise storage rate to GHS 0.30/GB/month.

Large files upload in 5 MB chunks (hosting file manager pattern) for the
transfer UI and Ladill Mail S2S API, with no app-level file size cap when
TRANSFER_MAX_FILE_BYTES=0.

Co-authored-by: Cursor <cursoragent@cursor.com>

resources/views/transfer/dashboard.blade.php

@@ -58,7 +58,7 @@
             <div class="rounded-2xl border border-indigo-100 bg-indigo-50/60 p-6">
                 <p class="text-xs font-medium uppercase tracking-wide text-indigo-600">Wallet balance</p>
                 <p class="mt-1.5 text-2xl font-semibold text-slate-900">{{ $fmt($balanceMinor) }}</p>
-                <p class="mt-2 text-sm text-slate-600">Storage is billed at GHS {{ number_format((float) config('transfer.price_per_gb_month', 0.15), 2) }} per GB per month from your Ladill wallet.</p>
+                <p class="mt-2 text-sm text-slate-600">Storage is billed at GHS {{ number_format((float) config('transfer.price_per_gb_month', 0.30), 2) }} per GB per month from your Ladill wallet.</p>
                 <div class="mt-4 space-y-3">
                     <a href="{{ route('transfer.transfers.create') }}" class="flex items-center justify-between rounded-xl border border-white bg-white px-4 py-3 text-sm hover:bg-indigo-50/50">
                         <span class="font-medium text-slate-700">New transfer</span>