refactor(tvix/nar-bridge): move pkg/server to pkg/http

This is only dealing with the HTTP interface.

Change-Id: I011b624fd9f11ea96231b92fea1166c118a219f2
Reviewed-on: https://cl.tvl.fyi/c/depot/+/9535
Tested-by: BuildkiteCI
Autosubmit: flokli <flokli@flokli.de>
Reviewed-by: Connor Brewster <cbrewster@hey.com>

tvix/nar-bridge/pkg/http/nar_get.go

@@ -1,4 +1,4 @@
-package server
+package http
 
 import (
 	"bytes"

tvix/nar-bridge/pkg/http/nar_put.go

@@ -1,4 +1,4 @@
-package server
+package http
 
 import (
 	"bufio"

tvix/nar-bridge/pkg/http/narinfo_get.go

@@ -1,4 +1,4 @@
-package server
+package http
 
 import (
 	"context"

tvix/nar-bridge/pkg/http/narinfo_put.go

@@ -1,4 +1,4 @@
-package server
+package http
 
 import (
 	"net/http"

tvix/nar-bridge/pkg/http/server.go

@@ -1,4 +1,4 @@
-package server
+package http
 
 import (
 	"context"

tvix/nar-bridge/pkg/http/util.go

@@ -1,4 +1,4 @@
-package server
+package http
 
 import (
 	"fmt"