Add Navigation Timing Performance Logging for Client-Side Route Loads

[Damilorlar]

##closed #575

Implement client-side page load performance logging using the Navigation Timing API to provide visibility into route load times across the application. This feature will emit structured debug-level logs after each full page load, enabling production logs to identify slow-loading routes and support performance monitoring.

The implementation should read the PerformanceNavigationTiming entry after the page's load event has completed and emit a structured log containing the following fields:
route
dom_content_loaded_ms
load_event_ms
time_to_first_byte_ms

Logging should occur only after the load event has fully completed, ensuring that timing metrics are complete and accurate. If navigation timing data is unavailable for a route, the logger should skip emitting a log without producing errors or warnings.

Acceptance Criteria
Emit a debug-level log after each full page load.
Include the fields: route, dom_content_loaded_ms, load_event_ms, and time_to_first_byte_ms.
Do not emit logs before the page load event completes.
Silently skip logging when PerformanceNavigationTiming data is unavailable

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