docs: consolidate documentation into organized structure

- Move 12 markdown files from root to docs/ subdirectories
- Organize documentation by category:
  • docs/troubleshooting/ (1 file)  - Technical troubleshooting guides
  • docs/deployment/      (4 files) - Deployment and security documentation
  • docs/guides/          (3 files) - Feature-specific guides
  • docs/planning/        (4 files) - Planning and improvement proposals

Root directory cleanup:
- Reduced from 16 to 4 markdown files in root
- Only essential project files remain:
  • CLAUDE.md (AI instructions)
  • README.md (Main project readme)
  • CLEANUP_PLAN.md (Current cleanup plan)
  • SRC_STRUCTURE_IMPROVEMENTS.md (Structure improvements)

This improves:
✅ Documentation discoverability
✅ Logical organization by purpose
✅ Clean root directory
✅ Better maintainability

src/Framework/Performance/Repository/PerformanceMetricsRepository.php

@@ -0,0 +1,218 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Framework\Performance\Repository;
+
+use App\Framework\Core\ValueObjects\Duration;
+use App\Framework\Database\ConnectionInterface;
+use App\Framework\Database\Migration\MigrationVersion;
+use App\Framework\Database\Query\QueryBuilder;
+use App\Framework\Database\Query\QueryBuilderFactory;
+use App\Framework\Performance\Entity\PerformanceMetric;
+use App\Framework\Performance\PerformanceCategory;
+use DateTimeImmutable;
+
+final readonly class PerformanceMetricsRepository
+{
+    private QueryBuilder $queryBuilder;
+
+    public function __construct(
+        private ConnectionInterface $connection,
+        private QueryBuilderFactory $queryBuilderFactory
+    ) {
+        $this->queryBuilder = $this->queryBuilderFactory->create($connection);
+    }
+
+    public function save(PerformanceMetric $metric): int
+    {
+        $data = [
+            'operation_id' => $metric->operationId,
+            'operation_type' => $metric->operationType,
+            'category' => $metric->category->value,
+            'migration_version' => $metric->migrationVersion?->toString(),
+            'execution_time_ms' => $metric->executionTime->toMilliseconds(),
+            'memory_start_bytes' => $metric->memoryStart->toBytes(),
+            'memory_end_bytes' => $metric->memoryEnd->toBytes(),
+            'memory_peak_bytes' => $metric->memoryPeak->toBytes(),
+            'memory_delta_bytes' => $metric->memoryDelta->toBytes(),
+            'success' => $metric->success,
+            'error_message' => $metric->errorMessage,
+            'metadata' => $metric->metadata ? json_encode($metric->metadata) : null,
+            'created_at' => $metric->createdAt->format('Y-m-d H:i:s'),
+            'updated_at' => $metric->updatedAt?->format('Y-m-d H:i:s'),
+        ];
+
+        return $this->queryBuilder
+            ->table('performance_metrics')
+            ->insert($data);
+    }
+
+    public function saveBatch(array $metrics): bool
+    {
+        if (empty($metrics)) {
+            return true;
+        }
+
+        $data = array_map(fn (PerformanceMetric $metric) => [
+            'operation_id' => $metric->operationId,
+            'operation_type' => $metric->operationType,
+            'category' => $metric->category->value,
+            'migration_version' => $metric->migrationVersion?->toString(),
+            'execution_time_ms' => $metric->executionTime->toMilliseconds(),
+            'memory_start_bytes' => $metric->memoryStart->toBytes(),
+            'memory_end_bytes' => $metric->memoryEnd->toBytes(),
+            'memory_peak_bytes' => $metric->memoryPeak->toBytes(),
+            'memory_delta_bytes' => $metric->memoryDelta->toBytes(),
+            'success' => $metric->success,
+            'error_message' => $metric->errorMessage,
+            'metadata' => $metric->metadata ? json_encode($metric->metadata) : null,
+            'created_at' => $metric->createdAt->format('Y-m-d H:i:s'),
+            'updated_at' => $metric->updatedAt?->format('Y-m-d H:i:s'),
+        ], $metrics);
+
+        return $this->queryBuilder
+            ->table('performance_metrics')
+            ->insertBatch($data) > 0;
+    }
+
+    public function findById(int $id): ?PerformanceMetric
+    {
+        $result = $this->queryBuilder
+            ->table('performance_metrics')
+            ->where('id', '=', $id)
+            ->first();
+
+        return $result ? PerformanceMetric::fromArray($result) : null;
+    }
+
+    public function findByOperationId(string $operationId): array
+    {
+        $results = $this->queryBuilder
+            ->table('performance_metrics')
+            ->where('operation_id', '=', $operationId)
+            ->orderBy('created_at', 'DESC')
+            ->get();
+
+        return array_map(
+            fn (array $row) => PerformanceMetric::fromArray($row),
+            $results
+        );
+    }
+
+    public function findByMigrationVersion(MigrationVersion $version): array
+    {
+        $results = $this->queryBuilder
+            ->table('performance_metrics')
+            ->where('migration_version', '=', $version->toString())
+            ->orderBy('created_at', 'DESC')
+            ->get();
+
+        return array_map(
+            fn (array $row) => PerformanceMetric::fromArray($row),
+            $results
+        );
+    }
+
+    public function findByCategory(PerformanceCategory $category, int $limit = 100): array
+    {
+        $results = $this->queryBuilder
+            ->table('performance_metrics')
+            ->where('category', '=', $category->value)
+            ->orderBy('created_at', 'DESC')
+            ->limit($limit)
+            ->get();
+
+        return array_map(
+            fn (array $row) => PerformanceMetric::fromArray($row),
+            $results
+        );
+    }
+
+    public function findFailures(int $limit = 50): array
+    {
+        $results = $this->queryBuilder
+            ->table('performance_metrics')
+            ->where('success', '=', false)
+            ->orderBy('created_at', 'DESC')
+            ->limit($limit)
+            ->get();
+
+        return array_map(
+            fn (array $row) => PerformanceMetric::fromArray($row),
+            $results
+        );
+    }
+
+    public function findSlowOperations(Duration $threshold, int $limit = 50): array
+    {
+        $results = $this->queryBuilder
+            ->table('performance_metrics')
+            ->where('execution_time_ms', '>', $threshold->toMilliseconds())
+            ->orderBy('execution_time_ms', 'DESC')
+            ->limit($limit)
+            ->get();
+
+        return array_map(
+            fn (array $row) => PerformanceMetric::fromArray($row),
+            $results
+        );
+    }
+
+    public function getAverageExecutionTime(PerformanceCategory $category): ?Duration
+    {
+        $result = $this->queryBuilder
+            ->table('performance_metrics')
+            ->where('category', '=', $category->value)
+            ->where('success', '=', true)
+            ->average('execution_time_ms');
+
+        return $result ? Duration::fromMilliseconds((int) $result) : null;
+    }
+
+    public function getPerformanceStatistics(DateTimeImmutable $since): array
+    {
+        $results = $this->queryBuilder
+            ->table('performance_metrics')
+            ->select([
+                'category',
+                'COUNT(*) as total_operations',
+                'AVG(execution_time_ms) as avg_execution_time',
+                'MAX(execution_time_ms) as max_execution_time',
+                'MIN(execution_time_ms) as min_execution_time',
+                'SUM(CASE WHEN success = 1 THEN 1 ELSE 0 END) as successful_operations',
+                'AVG(memory_peak_bytes) as avg_memory_peak',
+            ])
+            ->where('created_at', '>=', $since->format('Y-m-d H:i:s'))
+            ->groupBy('category')
+            ->get();
+
+        return array_map(function (array $row) {
+            return [
+                'category' => PerformanceCategory::from($row['category']),
+                'total_operations' => (int) $row['total_operations'],
+                'avg_execution_time' => Duration::fromMilliseconds((int) $row['avg_execution_time']),
+                'max_execution_time' => Duration::fromMilliseconds((int) $row['max_execution_time']),
+                'min_execution_time' => Duration::fromMilliseconds((int) $row['min_execution_time']),
+                'successful_operations' => (int) $row['successful_operations'],
+                'success_rate' => (float) $row['successful_operations'] / (float) $row['total_operations'],
+                'avg_memory_peak' => \App\Framework\Core\ValueObjects\Byte::fromBytes((int) $row['avg_memory_peak']),
+            ];
+        }, $results);
+    }
+
+    public function deleteOlderThan(DateTimeImmutable $cutoff): int
+    {
+        return $this->queryBuilder
+            ->table('performance_metrics')
+            ->where('created_at', '<', $cutoff->format('Y-m-d H:i:s'))
+            ->delete();
+    }
+
+    public function count(): int
+    {
+        return $this->queryBuilder
+            ->table('performance_metrics')
+            ->count();
+    }
+}