Feature Request: Add Statistics to API

## Summary The blocky API currently doesn't expose runtime statistics. To build dashboards on [blocky-ui](https://github.com/GabeDuarteM/blocky-ui), I'm currently parsing the Prometheus `/metrics` endpoint directly, which requires implementing a custom parser for the Prometheus text format. It would be helpful to have this data available via a REST API endpoint. ## Data Currently Missing from the API The following information is only available via Prometheus metrics: ### Query Statistics - **Total queries** (`blocky_query_total`) - total DNS queries processed - **Blocked queries** (`blocky_response_total{response_type="BLOCKED"}`) - queries that were blocked ### Cache Statistics - **Cache hits** (`blocky_cache_hits_total`) - **Cache misses** (`blocky_cache_misses_total`) ### List Statistics - **Denylist entries per group** (`blocky_denylist_cache_entries{group="..."}`) - number of blocked domains per group > **Nice to have:** For query/cache stats, it would be useful to have these scoped to the last 24h instead of cumulative since startup - this makes dashboard stats more meaningful for day-to-day usage. ## Context This data is already being tracked internally for Prometheus. Having it available as JSON would make it easier to build dashboards without requiring Prometheus text format parsing. ### Current Approach in blocky-ui We display the following header: <img width="1041" height="244" alt="Image" src="https://github.com/user-attachments/assets/fdaa42a2-1499-47a8-b69a-18d2e9283356" /> **Data sources:** - **Total queries & blocked**: Query logs (from last 24h), falls back to Prometheus runtime totals if Query logs are disabled - **Cache & list stats**: Prometheus metrics **Current limitations:** - If Prometheus is disabled (the default), we hide this entire panel - Runtime totals are less useful than time-scoped stats for day-to-day monitoring ### Proposed Improvement Having these stats in the API would allow us to always show this panel, regardless of Prometheus configuration. --- I'm also familiar with Go and happy to contribute if that's helpful 😄