Move internal packages to an internal folder

For reference: https://go.dev/doc/go1.4#internalpackages

ui/entry_scraper.go

@@ -1,70 +0,0 @@
-// SPDX-FileCopyrightText: Copyright The Miniflux Authors. All rights reserved.
-// SPDX-License-Identifier: Apache-2.0
-
-package ui // import "miniflux.app/v2/ui"
-
-import (
-	"net/http"
-
-	"miniflux.app/v2/http/request"
-	"miniflux.app/v2/http/response/json"
-	"miniflux.app/v2/locale"
-	"miniflux.app/v2/model"
-	"miniflux.app/v2/proxy"
-	"miniflux.app/v2/reader/processor"
-	"miniflux.app/v2/storage"
-)
-
-func (h *handler) fetchContent(w http.ResponseWriter, r *http.Request) {
-	loggedUserID := request.UserID(r)
-	entryID := request.RouteInt64Param(r, "entryID")
-
-	entryBuilder := h.store.NewEntryQueryBuilder(loggedUserID)
-	entryBuilder.WithEntryID(entryID)
-	entryBuilder.WithoutStatus(model.EntryStatusRemoved)
-
-	entry, err := entryBuilder.GetEntry()
-	if err != nil {
-		json.ServerError(w, r, err)
-		return
-	}
-
-	if entry == nil {
-		json.NotFound(w, r)
-		return
-	}
-
-	user, err := h.store.UserByID(entry.UserID)
-	if err != nil {
-		json.ServerError(w, r, err)
-	}
-	if user == nil {
-		json.NotFound(w, r)
-	}
-
-	feedBuilder := storage.NewFeedQueryBuilder(h.store, loggedUserID)
-	feedBuilder.WithFeedID(entry.FeedID)
-	feed, err := feedBuilder.GetFeed()
-	if err != nil {
-		json.ServerError(w, r, err)
-		return
-	}
-
-	if feed == nil {
-		json.NotFound(w, r)
-		return
-	}
-
-	if err := processor.ProcessEntryWebPage(feed, entry, user); err != nil {
-		json.ServerError(w, r, err)
-		return
-	}
-
-	if err := h.store.UpdateEntryContent(entry); err != nil {
-		json.ServerError(w, r, err)
-	}
-
-	readingTime := locale.NewPrinter(user.Language).Plural("entry.estimated_reading_time", entry.ReadingTime, entry.ReadingTime)
-
-	json.OK(w, r, map[string]string{"content": proxy.ProxyRewriter(h.router, entry.Content), "reading_time": readingTime})
-}