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>

tests/Unit/Module/LayoutNavProviderGuardTest.php

@@ -0,0 +1,110 @@
+<?php
+
+namespace MintyPHP\Tests\Unit\Module;
+
+use MintyPHP\App\AppContainer;
+use MintyPHP\App\Module\Contracts\LayoutContextProvider;
+use MintyPHP\App\Module\ModuleRegistry;
+use MintyPHP\Tests\Support\AppContainerIsolationTrait;
+use PHPUnit\Framework\TestCase;
+
+final class LayoutNavProviderGuardTest extends TestCase
+{
+    use AppContainerIsolationTrait;
+
+    private string $fixturesDir = '';
+
+    protected function setUp(): void
+    {
+        $this->fixturesDir = sys_get_temp_dir() . '/layout-provider-guard-' . uniqid();
+        mkdir($this->fixturesDir, 0777, true);
+    }
+
+    protected function tearDown(): void
+    {
+        $this->removeDir($this->fixturesDir);
+        $this->restoreAppContainer();
+    }
+
+    public function testReservedLayoutKeyIsRejected(): void
+    {
+        $registry = $this->createRegistryWithProvider(DummyReservedLayoutProvider::class);
+        $container = new AppContainer();
+        $container->set(ModuleRegistry::class, static fn (): ModuleRegistry => $registry);
+        $this->pushAppContainer($container);
+
+        $this->expectException(\RuntimeException::class);
+        $this->expectExceptionMessage("must not override reserved layout key 'moduleSlots'");
+
+        appBuildLayoutNavContext([], [], []);
+    }
+
+    public function testNamespacedLayoutProviderKeyIsAccepted(): void
+    {
+        $registry = $this->createRegistryWithProvider(DummyNamespacedLayoutProvider::class);
+        $container = new AppContainer();
+        $container->set(ModuleRegistry::class, static fn (): ModuleRegistry => $registry);
+        $this->pushAppContainer($container);
+
+        $layoutNav = appBuildLayoutNavContext([], [], []);
+
+        self::assertSame('ok', $layoutNav['dummy.value'] ?? null);
+    }
+
+    private function createRegistryWithProvider(string $providerClass): ModuleRegistry
+    {
+        $moduleDir = $this->fixturesDir . '/dummy-module';
+        mkdir($moduleDir, 0777, true);
+        file_put_contents(
+            $moduleDir . '/module.php',
+            '<?php return ' . var_export([
+                'id' => 'dummy-module',
+                'layout_context_providers' => [$providerClass],
+            ], true) . ';'
+        );
+
+        return ModuleRegistry::boot($this->fixturesDir, ['dummy-module']);
+    }
+
+    private function removeDir(string $dir): void
+    {
+        if (!is_dir($dir)) {
+            return;
+        }
+
+        $items = new \RecursiveIteratorIterator(
+            new \RecursiveDirectoryIterator($dir, \FilesystemIterator::SKIP_DOTS),
+            \RecursiveIteratorIterator::CHILD_FIRST
+        );
+
+        foreach ($items as $item) {
+            if ($item->isDir()) {
+                rmdir($item->getPathname());
+            } else {
+                unlink($item->getPathname());
+            }
+        }
+
+        rmdir($dir);
+    }
+}
+
+final class DummyReservedLayoutProvider implements LayoutContextProvider
+{
+    public function provide(array $session, AppContainer $container): array
+    {
+        return [
+            'moduleSlots' => ['bad' => true],
+        ];
+    }
+}
+
+final class DummyNamespacedLayoutProvider implements LayoutContextProvider
+{
+    public function provide(array $session, AppContainer $container): array
+    {
+        return [
+            'dummy.value' => 'ok',
+        ];
+    }
+}