feat: store pow performance statistics against statistics

db/db-core/src/lib.rs

@@ -250,6 +250,30 @@ pub trait MCDatabase: std::marker::Send + std::marker::Sync + CloneSPDatabase {
 
     /// fetch PoWConfig confirms
     async fn fetch_confirm(&self, user: &str, key: &str) -> DBResult<Vec<i64>>;
+
+    /// record PoW timing
+    async fn analysis_save(
+        &self,
+        captcha_id: &str,
+        d: &PerformanceAnalytics,
+    ) -> DBResult<()>;
+
+    /// fetch PoW analytics
+    async fn analytics_fetch(
+        &self,
+        captcha_id: &str,
+    ) -> DBResult<Vec<PerformanceAnalytics>>;
+}
+
+#[derive(Debug, Clone, Default, Deserialize, Serialize, PartialEq)]
+/// Proof-of-Work CAPTCHA performance analytics
+pub struct PerformanceAnalytics {
+    /// time taken to generate proof
+    pub time: u32,
+    /// difficulty factor for which the proof was generated
+    pub difficulty_factor: u32,
+    /// worker/client type: wasm, javascript, python, etc.
+    pub worker_type: String,
 }
 
 #[derive(Debug, Clone, Default, Deserialize, Serialize, PartialEq)]