feat(helpdesk): add handover protocol management

Implement handover protocols as a new entity in the helpdesk module,
allowing users to create fillable protocol records from admin-defined
software product schemas.

Key additions:
- DB migration (helpdesk_handovers table) with tenant scope
- HandoverService with status workflow (draft/in_progress/completed/archived)
- Three-tier permissions (view/create/manage)
- Two-step creation wizard (Stripe-style assistant)
- Grid.js list page with search and status filter
- Edit/detail page with aside metadata and status controls
- Reusable core autocomplete lookup component (app-lookup-field)
- Debitor lookup data endpoint for autocomplete
- Dynamic form rendering from schema snapshots
- 11 PHPUnit tests for HandoverService
- DE+EN i18n translations (48 keys each)

Also includes: PHPStan fixes (dead code removal, stale baseline cleanup),
software product edit title improvement, fieldset simplification,
and Stripe-style hover for schema preview.

Workflow: HD-HANDOVERS-001 (.agents/runs/HD-HANDOVERS-001/)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

phpstan-baseline.neon

@@ -1974,12 +1974,6 @@ parameters:
 			count: 1
 			path: modules/helpdesk/lib/Module/Helpdesk/Service/HelpdeskSettingsGateway.php
 
-		-
-			message: '#^Public method "MintyPHP\\Module\\Helpdesk\\Service\\HelpdeskSettingsGateway\:\:isConfigured\(\)" is never used$#'
-			identifier: public.method.unused
-			count: 1
-			path: modules/helpdesk/lib/Module/Helpdesk/Service/HelpdeskSettingsGateway.php
-
 		-
 			message: '#^Public method "MintyPHP\\Module\\Helpdesk\\Service\\HelpdeskSettingsGateway\:\:setAuthMode\(\)" is never used$#'
 			identifier: public.method.unused