test: add Pest browser testing with SQLite :memory: schema

Set up end-to-end browser testing using Pest Browser Plugin + Playwright.
New v4 test suite uses SQLite :memory: database with pre-generated schema dump
(database/schema/testing-schema.sql) instead of running migrations, enabling
faster test startup.

- Add pestphp/pest-plugin-browser dependency
- Create GenerateTestingSchema command to export PostgreSQL schema to SQLite
- Add .env.testing configuration for isolated test environment
- Implement v4 test directory structure (Feature, Browser, Unit tests)
- Update Pest skill documentation with browser testing patterns, API reference,
  debugging techniques, and common pitfalls
- Configure phpunit.xml and tests/Pest.php for v4 suite
- Update package.json and docker-compose.dev.yml for testing dependencies

database/migrations/2024_11_11_125366_add_index_to_activity_log.php

@@ -8,6 +8,10 @@ class AddIndexToActivityLog extends Migration
 {
     public function up()
     {
+        if (DB::connection()->getDriverName() !== 'pgsql') {
+            return;
+        }
+
         try {
             DB::statement('ALTER TABLE activity_log ALTER COLUMN properties TYPE jsonb USING properties::jsonb');
             DB::statement('CREATE INDEX idx_activity_type_uuid ON activity_log USING GIN (properties jsonb_path_ops)');
@@ -18,6 +22,10 @@ class AddIndexToActivityLog extends Migration
 
     public function down()
     {
+        if (DB::connection()->getDriverName() !== 'pgsql') {
+            return;
+        }
+
         try {
             DB::statement('DROP INDEX IF EXISTS idx_activity_type_uuid');
             DB::statement('ALTER TABLE activity_log ALTER COLUMN properties TYPE json USING properties::json');

database/migrations/2025_12_08_135600_add_performance_indexes.php

@@ -22,6 +22,10 @@ return new class extends Migration
 
     public function up(): void
     {
+        if (DB::connection()->getDriverName() !== 'pgsql') {
+            return;
+        }
+
         foreach ($this->indexes as [$table, $columns, $indexName]) {
             if (! $this->indexExists($indexName)) {
                 $columnList = implode(', ', array_map(fn ($col) => "\"$col\"", $columns));
@@ -32,6 +36,10 @@ return new class extends Migration
 
     public function down(): void
     {
+        if (DB::connection()->getDriverName() !== 'pgsql') {
+            return;
+        }
+
         foreach ($this->indexes as [, , $indexName]) {
             DB::statement("DROP INDEX IF EXISTS \"{$indexName}\"");
         }