Remove unused recycle bin and add optional local file delete (#26)

Soft-delete restore/purge/list and the recycle_purge job are gone.
Admin delete now removes library index rows, with an optional
delete_files query that also deletes local media + sidecar NFO.
UI copy is renamed from 移入回收站 to 删除, with a confirm checkbox.

Co-authored-by: Cursor Agent <cursoragent@cursor.com>
Co-authored-by: truewhile <truewhile@users.noreply.github.com>

internal/handler/routes_authenticated_features.go

@@ -20,7 +20,7 @@ func registerAuthedDLNARoutes(authed *gin.RouterGroup, svc *service.Container) {
 	authed.POST("/dlna/cast", dlnaCastHandler(svc))
 }
 
-func registerAuthedRecycleAndRealtimeRoutes(authed *gin.RouterGroup, svc *service.Container) {
+func registerAuthedRealtimeRoutes(authed *gin.RouterGroup, svc *service.Container) {
 	authed.GET("/ws", wsHandler(svc))
 	authed.GET("/events", sseHandler(svc))
 }