feat: Add runtime metrics for HTTP requests and database queries (v0.1.0)

- Add RuntimeCollector class for tracking request lifecycle metrics
- Add wordpress_http_requests_total counter (method, status, endpoint)
- Add wordpress_http_request_duration_seconds histogram
- Add wordpress_db_queries_total counter (endpoint)
- Add wordpress_db_query_duration_seconds histogram (requires SAVEQUERIES)
- Update Collector to expose stored runtime metrics
- Add new settings options for enabling/disabling runtime metrics
- Create translation files (.pot, .po, .mo) for internationalization
- Update documentation and changelog

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

README.md

@@ -71,6 +71,8 @@ scrape_configs:
 
 ## Default Metrics
 
+### Static Metrics
+
 | Metric | Type | Labels | Description |
 |--------|------|--------|-------------|
 | wordpress_info | Gauge | version, php_version, multisite | WordPress installation info |
@@ -79,6 +81,17 @@ scrape_configs:
 | wordpress_comments_total | Gauge | status | Total comments by status |
 | wordpress_plugins_total | Gauge | status | Total plugins (active/inactive) |
 
+### Runtime Metrics (v0.1.0+)
+
+| Metric | Type | Labels | Description |
+|--------|------|--------|-------------|
+| wordpress_http_requests_total | Counter | method, status, endpoint | Total HTTP requests |
+| wordpress_http_request_duration_seconds | Histogram | method, endpoint | Request duration distribution |
+| wordpress_db_queries_total | Counter | endpoint | Total database queries |
+| wordpress_db_query_duration_seconds | Histogram | endpoint | Query duration (requires SAVEQUERIES) |
+
+**Note:** Runtime metrics aggregate data across requests. Enable only the metrics you need to minimize performance impact.
+
 ## Extending with Custom Metrics
 
 Add your own metrics using the `wp_prometheus_collect_metrics` action: