Download REST API endpoints (#72)

* backend and frontend hotfixes, see message

Improved rendering on the frontend by cutting unecessary useStates.
Backend side, downloads now auto resume even on application kill.

* download rest api endpoints, general code refactor

* download request json mappings

server/rest/container.go

@@ -0,0 +1,25 @@
+package rest
+
+import (
+	"github.com/go-chi/chi/v5"
+	"github.com/marcopeocchi/yt-dlp-web-ui/server/internal"
+	middlewares "github.com/marcopeocchi/yt-dlp-web-ui/server/middleware"
+)
+
+func Container(db *internal.MemoryDB, mq *internal.MessageQueue) *Handler {
+	var (
+		service = ProvideService(db, mq)
+		handler = ProvideHandler(service)
+	)
+	return handler
+}
+
+func ApplyRouter(db *internal.MemoryDB, mq *internal.MessageQueue) func(chi.Router) {
+	h := Container(db, mq)
+
+	return func(r chi.Router) {
+		r.Use(middlewares.Authenticated)
+		r.Post("/exec", h.Exec())
+		r.Get("/running", h.Running())
+	}
+}