Backend module: CSV import for the VITEC domain models

New "VITEC Import" module under Web: one import page per domain model
(v1: Market, Solution, Product - registry-driven, adding a model is one
config entry). Workflow: upload a CSV (delimiter and encoding are
auto-detected, including German-Excel semicolon/Windows-1252), map CSV
columns to DB fields, persist the mapping per model together with the
identity field used for matching (new table tx_vitec_import_mapping,
no TCA - pure tool configuration), review a unified list of CSV rows
matched against the DB records (new / update with differing fields /
unchanged / db-only), then apply the checked rows through DataHandler.

Each importable row carries an editable JSON payload textarea - what
is written is the textarea content, not the raw CSV, so editors can
fix values right in the review step. The parsed CSV travels through
the form as a hidden JSON field: no session state, no temp files.
Importable fields are derived from TCA at runtime (scalar types only;
files, categories and other relations are excluded - a flat CSV
cannot carry them). Payloads are whitelisted against that field list
on apply; new records require a storage pid (prefilled from existing
records). BE user permissions apply via DataHandler.

Deliberately out of v1: import log with three-way compare (protection
against overwriting manual edits), images/relations, multiple saved
mappings per model.

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

packages/vitec/Configuration/Backend/Modules.php

@@ -2,9 +2,32 @@
 
 declare(strict_types=1);
 
+use Evomedien\Vitec\Controller\Backend\ImportController;
 use Evomedien\Vitec\Controller\OgImageController;
 
 return [
+    'web_vitecimport' => [
+        'parent'         => 'web',
+        'position'       => ['after' => 'web_info'],
+        'access'         => 'user',
+        'workspaces'     => 'live',
+        'path'           => '/module/web/vitec-import',
+        'labels'         => [
+            'title' => 'VITEC Import',
+            'shortDescription' => 'CSV import for the VITEC domain models',
+        ],
+        'extensionName'  => 'Vitec',
+        'iconIdentifier' => 'vitec-import',
+        'routes'         => [
+            '_default' => [
+                'target' => ImportController::class . '::indexAction',
+            ],
+            'process' => [
+                'target' => ImportController::class . '::processAction',
+                'methods' => ['POST'],
+            ],
+        ],
+    ],
     'web_vitecogimage' => [
         'parent'         => 'web',
         'position'       => ['after' => 'web_info'],