feat: extend module platform with UI slots, runtime components, CLI tooling and {{userId}} search support

Completes the generic module platform that enables modules to contribute
UI elements, runtime JS components, and search resources without any
core hardcoding.

New generic UI slot types:
- topbar.right_item: module-contributed topbar buttons
- layout.body_end_template: module-contributed dialog/overlay templates
- layout.head_style: module-contributed global CSS
- runtime.component: declarative JS component registration with phase ordering

New infrastructure:
- ModuleAutoloader: PSR-4 autoloading for module-local PHP classes
- ModuleRuntimePageBuilder: symlinks module pages into runtime directory
- ModuleRuntimeAssetPublisher: publishes module CSS/JS to web/modules/
- ModulePermissionSynchronizer: syncs module permissions to DB
- CLI scripts: module-runtime-sync, module-build, module-migrate,
  module-permissions-sync, module-assets-sync
- {{userId}} placeholder in SearchDataService for user-scoped search queries
- Component runtime with phased initialization (early/default/late)
- AppContainer.protectExistingBindings() to prevent module→core overwrites
- Architecture tests: ModuleStructureContractTest, CoreTemplateIsolationTest,
  FrontendComponentRuntimeContractTest, AppContainerIsolationContractTest

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

pages/admin/users/_form.phtml

@@ -122,7 +122,7 @@ foreach ($tenants as $tenant) {
 
 ?>
 <form id="<?php e($formId); ?>" method="post" data-details-storage="admin-user-form-details-v1" data-standard-detail-form="1">
-  <div class="app-tabs" data-tabs data-tabs-param="tab" data-tabs-storage-key="admin-user-form"<?php if (!empty($ignoreTabStorage)) { echo ' data-tabs-ignore-storage'; } ?>>
+  <div class="app-tabs" data-tabs data-app-component="tabs" data-tabs-param="tab" data-tabs-storage-key="admin-user-form"<?php if (!empty($ignoreTabStorage)) { echo ' data-tabs-ignore-storage'; } ?>>
     <div class="app-tabs-nav">
       <button type="button" data-tab="profile" data-tab-default><?php e(t('Master data')); ?></button>
       <?php if ($showOrganizationTab): ?>