Fix systemic extraction breakage in authenticated UI.

The give→merchant transform left several independent breakages that 500'd
once a logged-in user hit the pages:

- /storefronts/{create,show,update,...} were wired to Qr\QrCodeController,
  which renders events-lineage qr-codes.* views referencing 14 undefined
  events.* routes. Rewire to StorefrontController (clean storefronts.* views).
- storefronts/show.blade.php @include('give.storefronts.partials.*') — the
  view dir was renamed give→merchant but the include namespace wasn't.
- /payouts + /search queried qr_sale_orders.*_minor; migration created *_ghs.
- Remove dead GiveDonation model (nonexistent give_donations table).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

app/Models/GiveDonation.php

@@ -1,59 +0,0 @@
-<?php
-
-namespace App\Models;
-
-use Illuminate\Database\Eloquent\Model;
-use Illuminate\Database\Eloquent\Relations\BelongsTo;
-
-class QrSaleOrder extends Model
-{
-    public const STATUS_PENDING = 'pending';
-    public const STATUS_PAID = 'paid';
-    public const STATUS_FAILED = 'failed';
-
-    /** Platform fee on orders (Ladill Merchant tier). */
-    public const PLATFORM_FEE_RATE = 0.09;
-
-    protected $fillable = [
-        'pay_order_id',
-        'qr_code_id',
-        'user_id',
-        'reference',
-        'collection_type',
-        'amount_minor',
-        'currency',
-        'platform_fee_minor',
-        'merchant_amount_minor',
-        'payer_name',
-        'payer_email',
-        'payer_phone',
-        'payer_note',
-        'status',
-        'payment_reference',
-        'paid_at',
-        'metadata',
-    ];
-
-    protected $casts = [
-        'amount_minor' => 'integer',
-        'platform_fee_minor' => 'integer',
-        'merchant_amount_minor' => 'integer',
-        'metadata' => 'array',
-        'paid_at' => 'datetime',
-    ];
-
-    public function qrCode(): BelongsTo
-    {
-        return $this->belongsTo(QrCode::class);
-    }
-
-    public function merchant(): BelongsTo
-    {
-        return $this->belongsTo(User::class, 'user_id');
-    }
-
-    public function amountMajor(): float
-    {
-        return $this->amount_minor / 100;
-    }
-}