http: serve under /api

This makes setting up rewrites easier.

main.go

@@ -25,8 +25,6 @@ var (
 	flagGitlabProject string
 )
 
-// https://git.flow3r.garden/api/v4/projects/flow3r%2Fflow3r-firmware/releases
-
 type GLAssetLink struct {
 	ID      int64  `json:"id"`
 	Name    string `json:"name"`
@@ -157,7 +155,7 @@ func (s *server) handleReleases(w http.ResponseWriter, r *http.Request) {
 }
 
 var (
-	reMirrorURL = regexp.MustCompile("^/release/([^/]+)/([^/]+.bin)$")
+	reMirrorURL = regexp.MustCompile("^/api/release/([^/]+)/([^/]+.bin)$")
 )
 
 func (s *server) cacheTarball(rel *GLRelease, data io.Reader) error {
@@ -285,8 +283,8 @@ func main() {
 	}
 	go s.run(ctx)
 
-	http.HandleFunc("/releases.json", s.handleReleases)
-	http.HandleFunc("/release/", s.handleReleaseMirror)
+	http.HandleFunc("/api/releases.json", s.handleReleases)
+	http.HandleFunc("/api/release/", s.handleReleaseMirror)
 	log.Printf("Listening on %s...", flagListen)
 	http.ListenAndServe(flagListen, nil)
 }