docs: dev-Doku für den Live-Betrieb neu sortiert — Archiv + Betrieb + Roadmap

Das System ist seit 20.07.2026 live; die dev-Doku spiegelt jetzt den
Betriebszustand statt der Release-Vorbereitung:

- dev/betrieb/: Deploy-Runbook (neu: §10 Betrieb nach Go-Live mit
  SFTP-Deploy-Checkliste inkl. queue:restart-Pflicht und den
  Betriebs-Erkenntnissen der Go-Live-Woche), Legacy-API-Parität, Umami.
- dev/roadmap.md: offene Nachlauf-Punkte (Go-Live-Mails, Merge nach main,
  Stripe-Test-Artefakte, Key-Rotation, Alt-System-Abschaltung) und
  Ideen-Backlog.
- dev/archive/: abgeschlossene Phasen — Migration-2026-Planung,
  Cutover-Runbook (mit Erledigt-Vermerk), Release-Plan/QA-Checkliste,
  Optimierungsphasen, Frontend-Konzepte + Responsive-Audits vom 16.07.,
  Altsystem-Reste.
- dev/README.md als Wegweiser; gitignore-Pfad der SQL-Dumps mitgezogen
  (dev/archive/migration-2026/sql/ bleibt untracked, ebenso dev/migration/
  und dev/api/).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

dev/_old/Models/InvoiceBillingAddress.php

@@ -1,89 +0,0 @@
-<?php
-
-/**
- * Created by Reliese Model.
- */
-
-namespace App\Models;
-
-use Carbon\Carbon;
-use Illuminate\Database\Eloquent\Collection;
-use Illuminate\Database\Eloquent\Model;
-
-/**
- * Class InvoiceBillingAddress
- *
- * @property int $id
- * @property int|null $salutation_id
- * @property string|null $title
- * @property string $name
- * @property string|null $address
- * @property string|null $address1
- * @property string|null $address2
- * @property string|null $postal_code
- * @property string|null $city
- * @property int|null $country_id
- * @property string|null $country_name
- * @property Carbon|null $created_at
- * @property Carbon|null $updated_at
- * @property Country|null $country
- * @property Salutation|null $salutation
- * @property Collection|Invoice[] $invoices
- * @property-read int|null $invoices_count
- *
- * @method static \Illuminate\Database\Eloquent\Builder|InvoiceBillingAddress newModelQuery()
- * @method static \Illuminate\Database\Eloquent\Builder|InvoiceBillingAddress newQuery()
- * @method static \Illuminate\Database\Eloquent\Builder|InvoiceBillingAddress query()
- * @method static \Illuminate\Database\Eloquent\Builder|InvoiceBillingAddress whereAddress($value)
- * @method static \Illuminate\Database\Eloquent\Builder|InvoiceBillingAddress whereAddress1($value)
- * @method static \Illuminate\Database\Eloquent\Builder|InvoiceBillingAddress whereAddress2($value)
- * @method static \Illuminate\Database\Eloquent\Builder|InvoiceBillingAddress whereCity($value)
- * @method static \Illuminate\Database\Eloquent\Builder|InvoiceBillingAddress whereCountryId($value)
- * @method static \Illuminate\Database\Eloquent\Builder|InvoiceBillingAddress whereCountryName($value)
- * @method static \Illuminate\Database\Eloquent\Builder|InvoiceBillingAddress whereCreatedAt($value)
- * @method static \Illuminate\Database\Eloquent\Builder|InvoiceBillingAddress whereId($value)
- * @method static \Illuminate\Database\Eloquent\Builder|InvoiceBillingAddress whereName($value)
- * @method static \Illuminate\Database\Eloquent\Builder|InvoiceBillingAddress wherePostalCode($value)
- * @method static \Illuminate\Database\Eloquent\Builder|InvoiceBillingAddress whereSalutationId($value)
- * @method static \Illuminate\Database\Eloquent\Builder|InvoiceBillingAddress whereTitle($value)
- * @method static \Illuminate\Database\Eloquent\Builder|InvoiceBillingAddress whereUpdatedAt($value)
- *
- * @mixin \Eloquent
- */
-class InvoiceBillingAddress extends Model
-{
-    protected $table = 'invoice_billing_address';
-
-    protected $casts = [
-        'salutation_id' => 'int',
-        'country_id' => 'int',
-    ];
-
-    protected $fillable = [
-        'salutation_id',
-        'title',
-        'name',
-        'address',
-        'address1',
-        'address2',
-        'postal_code',
-        'city',
-        'country_id',
-        'country_name',
-    ];
-
-    public function country()
-    {
-        return $this->belongsTo(Country::class);
-    }
-
-    public function salutation()
-    {
-        return $this->belongsTo(Salutation::class);
-    }
-
-    public function invoices()
-    {
-        return $this->hasMany(Invoice::class, 'billing_address_id');
-    }
-}