Improve logging

- Actually log useful information at their respective log level.
- Add logs in hot-paths to be able to deep-dive and debug specific
requests (see server/handler.go)
- Remove zerologger and instead use custom logger that doesn't log
JSON (directly inspired by https://codeberg.org/Codeberg/moderation/pulls/7).
- Add more information to existing fields(e.g. the host that the user is
visiting, this was noted by @fnetX).

server/setup.go

@@ -2,21 +2,21 @@ package server
 
 import (
 	"bytes"
+	"fmt"
 	"net/http"
 	"time"
 
-	"github.com/rs/zerolog/log"
-
 	"github.com/valyala/fasthttp"
 
 	"codeberg.org/codeberg/pages/server/cache"
+	"codeberg.org/codeberg/pages/server/log"
 	"codeberg.org/codeberg/pages/server/utils"
 )
 
 type fasthttpLogger struct{}
 
 func (fasthttpLogger) Printf(format string, args ...interface{}) {
-	log.Printf("[FASTHTTP] "+format, args...)
+	log.Info("FastHTTP: %s", fmt.Sprintf(format, args...))
 }
 
 func SetupServer(handler fasthttp.RequestHandler) *fasthttp.Server {