fix: add warn levels to observability logs

integrations/jikan/client.go

@@ -158,6 +158,9 @@ func logJikanCache(cacheKey string, source string, startedAt time.Time, err erro
 	level := observability.LogLevelInfo
 	if err != nil {
 		level = observability.LogLevelError
+	} else if source != "fresh" && source != "refresh" {
+		// Stale reads are expected sometimes, but worth tracking in logs.
+		level = observability.LogLevelWarn
 	}
 
 	observability.LogJSON(
@@ -181,8 +184,10 @@ func logJikanUpstream(urlStr string, statusCode int, attempts int, startedAt tim
 	}
 
 	level := observability.LogLevelInfo
-	if err != nil || statusCode >= http.StatusBadRequest {
+	if err != nil || statusCode >= http.StatusInternalServerError {
 		level = observability.LogLevelError
+	} else if statusCode == http.StatusTooManyRequests || statusCode >= http.StatusBadRequest {
+		level = observability.LogLevelWarn
 	}
 
 	observability.LogJSON(

internal/server/observability.go

@@ -23,8 +23,16 @@ func RequestLogger(metrics *observability.Metrics) gin.HandlerFunc {
 		duration := time.Since(start)
 		metrics.ObserveHTTPRequest(c.Request.Method, route, c.Writer.Status(), duration)
 
+		level := observability.LogLevelInfo
+		status := c.Writer.Status()
+		if status >= 500 {
+			level = observability.LogLevelError
+		} else if status >= 400 {
+			level = observability.LogLevelWarn
+		}
+
 		observability.LogJSON(
-			observability.LogLevelInfo,
+			level,
 			"http_request",
 			"http",
 			"",
@@ -33,7 +41,7 @@ func RequestLogger(metrics *observability.Metrics) gin.HandlerFunc {
 				"route":       route,
 				"path":        path,
 				"query":       query,
-				"status":      c.Writer.Status(),
+				"status":      status,
 				"duration_ms": float64(duration.Microseconds()) / 1000,
 				"bytes":       c.Writer.Size(),
 				"client_ip":   c.ClientIP(),