Serve the add-on via the web interface

Serve the Blender add-on via the web interface, downloadable from
`/flamenco-addon.zip`.

cmd/flamenco-manager/main.go

@@ -303,6 +303,9 @@ func buildWebService(
 		return c.Redirect(http.StatusTemporaryRedirect, "/app/")
 	})
 
+	// Serve the Blender add-on. It's contained in the static files of the webapp.
+	e.GET("/flamenco-addon.zip", echo.WrapHandler(webAppHandler))
+
 	// Redirect / to the webapp.
 	e.GET("/", func(c echo.Context) error {
 		return c.Redirect(http.StatusTemporaryRedirect, "/app/")

web/app/src/App.vue

@@ -17,6 +17,7 @@
     <api-spinner />
     <span class="app-version">
       version: {{ flamencoVersion }}
+      | <a href="/api/swagger-ui/">API</a>
     </span>
   </header>
   <router-view></router-view>