[performance] more logging tweaks (#4415)

- reduces number of necessary function calls by moving log level checking out of the uninlineable `logf(...)` function and into each of its caller (which are all inlined). this in turn means the log level check is performed in-situ wherever a call to `log.Debug(...)` (etc) is made, reduce unnecessary calls when a certain log level is disabled.
- sets the http.Server{}.ErrorLog to output to our internal logging package (which in turn ensures it gets wrapped in either our logfmt or json log formatting)

Reviewed-on: https://codeberg.org/superseriousbusiness/gotosocial/pulls/4415
Co-authored-by: kim <grufwub@gmail.com>
Co-committed-by: kim <grufwub@gmail.com>

internal/router/router.go

@@ -23,6 +23,7 @@ import (
 	"fmt"
 	"net"
 	"net/http"
+	"strconv"
 	"time"
 
 	"code.superseriousbusiness.org/gotosocial/internal/config"
@@ -93,9 +94,10 @@ func New(ctx context.Context) (*Router, error) {
 	// `server start` command anyway.
 	baseCtx := func(_ net.Listener) context.Context { return ctx }
 
-	addr := fmt.Sprintf("%s:%d",
+	// Create joined listen addr.
+	addr := net.JoinHostPort(
 		config.GetBindAddress(),
-		config.GetPort(),
+		strconv.Itoa(config.GetPort()),
 	)
 
 	// Wrap the gin engine handler in our
@@ -111,6 +113,7 @@ func New(ctx context.Context) (*Router, error) {
 		WriteTimeout:      writeTimeout,
 		IdleTimeout:       idleTimeout,
 		BaseContext:       baseCtx,
+		ErrorLog:          log.NewStdLogger(log.ERROR),
 	}
 
 	return &Router{