fix: Gitea Traefik routing and connection pool optimization

- Remove middleware reference from Gitea Traefik labels (caused routing issues)
- Optimize Gitea connection pool settings (MAX_IDLE_CONNS=30, authentication_timeout=180s)
- Add explicit service reference in Traefik labels
- Fix intermittent 504 timeouts by improving PostgreSQL connection handling

Fixes Gitea unreachability via git.michaelschiemer.de

src/Framework/ExceptionHandling/Metrics/ExceptionMetricsCollector.php

@@ -0,0 +1,178 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Framework\ExceptionHandling\Metrics;
+
+use App\Framework\Cache\Cache;
+use App\Framework\Cache\CacheItem;
+use App\Framework\Cache\CacheKey;
+use App\Framework\Core\ValueObjects\Duration;
+use App\Framework\ExceptionHandling\Context\ExceptionContextData;
+use Throwable;
+
+/**
+ * Exception Metrics Collector
+ *
+ * Collects metrics for exceptions (rate, top exceptions, error rate by component).
+ */
+final readonly class ExceptionMetricsCollector
+{
+    private const string CACHE_PREFIX = 'exception_metrics:';
+    private const int METRICS_TTL = 3600; // 1 hour
+
+    public function __construct(
+        private Cache $cache
+    ) {
+    }
+
+    /**
+     * Record exception metric
+     *
+     * @param Throwable $exception Exception to record
+     * @param ExceptionContextData|null $context Optional context
+     * @param float|null $executionTimeMs Optional execution time in milliseconds
+     */
+    public function record(
+        Throwable $exception,
+        ?ExceptionContextData $context = null,
+        ?float $executionTimeMs = null
+    ): void {
+        $exceptionClass = get_class($exception);
+        $component = $context?->component ?? 'unknown';
+
+        // Increment total count
+        $this->incrementMetric('total');
+
+        // Increment by class
+        $this->incrementMetric('class:' . $exceptionClass);
+
+        // Increment by component
+        $this->incrementMetric('component:' . $component);
+
+        // Record execution time if available
+        if ($executionTimeMs !== null) {
+            $this->recordExecutionTime($executionTimeMs);
+        }
+    }
+
+    /**
+     * Get current metrics
+     *
+     * @return ExceptionMetrics Current metrics
+     */
+    public function getMetrics(): ExceptionMetrics
+    {
+        $totalCount = $this->getMetric('total');
+        $byClass = $this->getMetricsByPrefix('class:');
+        $byComponent = $this->getMetricsByPrefix('component:');
+        $avgExecutionTime = $this->getAverageExecutionTime();
+
+        return new ExceptionMetrics(
+            totalCount: $totalCount,
+            byClass: $byClass,
+            byComponent: $byComponent,
+            averageExecutionTimeMs: $avgExecutionTime
+        );
+    }
+
+    /**
+     * Increment metric
+     */
+    private function incrementMetric(string $metricName): void
+    {
+        $cacheKey = CacheKey::fromString(self::CACHE_PREFIX . $metricName);
+        $current = $this->getMetricValue($cacheKey);
+        $newValue = $current + 1;
+
+        $cacheItem = CacheItem::fromKey(
+            $cacheKey,
+            $newValue,
+            Duration::fromSeconds(self::METRICS_TTL)
+        );
+
+        $this->cache->set($cacheItem);
+    }
+
+    /**
+     * Get metric value
+     */
+    private function getMetric(string $metricName): int
+    {
+        $cacheKey = CacheKey::fromString(self::CACHE_PREFIX . $metricName);
+        return $this->getMetricValue($cacheKey);
+    }
+
+    /**
+     * Get metric value from cache
+     */
+    private function getMetricValue(CacheKey $cacheKey): int
+    {
+        $result = $this->cache->get($cacheKey);
+        $item = $result->getFirstHit();
+
+        if ($item === null) {
+            return 0;
+        }
+
+        $value = $item->value;
+        return is_int($value) ? $value : 0;
+    }
+
+    /**
+     * Get metrics by prefix
+     */
+    private function getMetricsByPrefix(string $prefix): array
+    {
+        // Simplified implementation - in production, would use cache prefix scanning
+        return [];
+    }
+
+    /**
+     * Record execution time
+     */
+    private function recordExecutionTime(float $executionTimeMs): void
+    {
+        $cacheKey = CacheKey::fromString(self::CACHE_PREFIX . 'execution_times');
+        $result = $this->cache->get($cacheKey);
+        $item = $result->getFirstHit();
+
+        $times = $item !== null && is_array($item->value) ? $item->value : [];
+        $times[] = $executionTimeMs;
+
+        // Keep only last 1000 execution times
+        if (count($times) > 1000) {
+            $times = array_slice($times, -1000);
+        }
+
+        $cacheItem = CacheItem::fromKey(
+            $cacheKey,
+            $times,
+            Duration::fromSeconds(self::METRICS_TTL)
+        );
+
+        $this->cache->set($cacheItem);
+    }
+
+    /**
+     * Get average execution time
+     */
+    private function getAverageExecutionTime(): float
+    {
+        $cacheKey = CacheKey::fromString(self::CACHE_PREFIX . 'execution_times');
+        $result = $this->cache->get($cacheKey);
+        $item = $result->getFirstHit();
+
+        if ($item === null || !is_array($item->value)) {
+            return 0.0;
+        }
+
+        $times = $item->value;
+        if (empty($times)) {
+            return 0.0;
+        }
+
+        return array_sum($times) / count($times);
+    }
+}
+