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/rpc/container.go

@@ -0,0 +1,24 @@
+package rpc
+
+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"
+)
+
+// Dependency injection container.
+func Container(db *internal.MemoryDB, mq *internal.MessageQueue) *Service {
+	return &Service{
+		db: db,
+		mq: mq,
+	}
+}
+
+// RPC service must be registered before applying this router!
+func ApplyRouter() func(chi.Router) {
+	return func(r chi.Router) {
+		r.Use(middlewares.Authenticated)
+		r.Get("/ws", WebSocket)
+		r.Post("/http", Post)
+	}
+}