[FEAT] Add onboarding wizard with visura camerale and CertiSource integration

- New 5-step onboarding wizard (onboarding.html) replacing setup-org.html
- Step 1: Choose data source (Upload Visura / CertiSource / Manual)
- Step 2: PDF upload with AI extraction or CertiSource P.IVA lookup
- Step 3: Verify/complete company data with NIS2 sector mapping
- Step 4: User profile completion
- Step 5: NIS2 classification (Essential/Important) with summary
- OnboardingController with upload-visura, fetch-company, complete endpoints
- VisuraService with Claude AI PDF extraction and ATECO-to-NIS2 mapping
- CertiSource API integration for automatic company data retrieval
- Updated login/register redirects to point to new onboarding wizard

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

public/index.php

@@ -97,6 +97,7 @@ $controllerMap = [
     'assets'        => 'AssetController',
     'audit'         => 'AuditController',
     'admin'         => 'AdminController',
+    'onboarding'    => 'OnboardingController',
 ];
 
 if (!isset($controllerMap[$controllerName])) {
@@ -265,6 +266,13 @@ $actionMap = [
         'GET:users'                 => 'listUsers',
         'GET:stats'                 => 'platformStats',
     ],
+
+    // ── OnboardingController ──────────────────────
+    'onboarding' => [
+        'POST:uploadVisura'  => 'uploadVisura',
+        'POST:fetchCompany'  => 'fetchCompany',
+        'POST:complete'      => 'complete',
+    ],
 ];
 
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