Add telemetry

internal/logging/logging.go

@@ -3,6 +3,7 @@ package logging
 import (
 	"context"
 	"encoding/json"
+	"io"
 	"net/http"
 	"os"
 	"strings"
@@ -28,7 +29,9 @@ type Config struct {
 // - File set: JSON → lumberjack rotating file
 // - File empty + TTY: colored ConsoleWriter → stderr
 // - File empty + not TTY: JSON → stderr (for systemd journal)
-func Setup(cfg Config) zerolog.Logger {
+// Extra writers (e.g., OTLP log bridge) are added via io.MultiWriter so logs
+// are written to both the primary destination and any extra writers.
+func Setup(cfg Config, extraWriters ...io.Writer) zerolog.Logger {
 	// Parse log level
 	level, err := zerolog.ParseLevel(cfg.Level)
 	if err != nil || cfg.Level == "" {
@@ -48,20 +51,32 @@ func Setup(cfg Config) zerolog.Logger {
 			MaxAge:     cfg.MaxAgeDays,
 			Compress:   cfg.Compress,
 		}
-		logger = zerolog.New(jack).With().Timestamp().Caller().Logger()
+		var w io.Writer = jack
+		if len(extraWriters) > 0 {
+			w = io.MultiWriter(append([]io.Writer{jack}, extraWriters...)...)
+		}
+		logger = zerolog.New(w).With().Timestamp().Caller().Logger()
 	} else {
 		fi, err := os.Stderr.Stat()
 		isTTY := err == nil && (fi.Mode()&os.ModeCharDevice) != 0
 		if isTTY {
-			// Dev mode: colored console
+			// Dev mode: colored console (extra writers get JSON, console gets pretty)
 			cw := zerolog.ConsoleWriter{
 				Out:        os.Stderr,
 				TimeFormat: time.RFC3339,
 			}
-			logger = zerolog.New(cw).With().Timestamp().Caller().Logger()
+			var w io.Writer = cw
+			if len(extraWriters) > 0 {
+				w = io.MultiWriter(append([]io.Writer{cw}, extraWriters...)...)
+			}
+			logger = zerolog.New(w).With().Timestamp().Caller().Logger()
 		} else {
 			// Systemd journal: JSON to stderr
-			logger = zerolog.New(os.Stderr).With().Timestamp().Caller().Logger()
+			var w io.Writer = os.Stderr
+			if len(extraWriters) > 0 {
+				w = io.MultiWriter(append([]io.Writer{os.Stderr}, extraWriters...)...)
+			}
+			logger = zerolog.New(w).With().Timestamp().Caller().Logger()
 		}
 	}