feat(phase-19/20): global search controller, search route, audit log migration (partial)

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01RdUGwo74JXChRCF88Yu27d

Author: claude

erp/database/migrations/2026_06_19_000001_create_audit_logs_table.php

@@ -0,0 +1,29 @@
+<?php
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration {
+    public function up(): void
+    {
+        Schema::dropIfExists('audit_logs');
+        Schema::create('audit_logs', function (Blueprint $table) {
+            $table->id();
+            $table->unsignedBigInteger('tenant_id')->index();
+            $table->unsignedBigInteger('user_id')->nullable();
+            $table->string('action'); // created, updated, deleted, viewed
+            $table->string('auditable_type');
+            $table->unsignedBigInteger('auditable_id');
+            $table->json('old_values')->nullable();
+            $table->json('new_values')->nullable();
+            $table->string('ip_address', 45)->nullable();
+            $table->string('user_agent')->nullable();
+            $table->timestamps();
+        });
+    }
+
+    public function down(): void
+    {
+        Schema::dropIfExists('audit_logs');
+    }
+};

erp/routes/api.php

@@ -322,5 +322,8 @@
 
         // Global Search
         Route::get('/search', [\App\Http\Controllers\Api\V1\SearchController::class, 'search']);
+
+        // Audit Logs
+        Route::get('/audit-logs', [\App\Http\Controllers\Api\V1\AuditLogController::class, 'index']);
     });
 });