Move internal packages to an internal folder

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

internal/ui/subscription_bookmarklet.go

@@ -0,0 +1,58 @@
+// SPDX-FileCopyrightText: Copyright The Miniflux Authors. All rights reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+package ui // import "miniflux.app/v2/internal/ui"
+
+import (
+	"net/http"
+
+	"miniflux.app/v2/internal/config"
+	"miniflux.app/v2/internal/http/request"
+	"miniflux.app/v2/internal/http/response/html"
+	"miniflux.app/v2/internal/ui/form"
+	"miniflux.app/v2/internal/ui/session"
+	"miniflux.app/v2/internal/ui/view"
+
+	"mvdan.cc/xurls/v2"
+)
+
+func (h *handler) bookmarklet(w http.ResponseWriter, r *http.Request) {
+	sess := session.New(h.store, request.SessionID(r))
+	view := view.New(h.tpl, r, sess)
+
+	user, err := h.store.UserByID(request.UserID(r))
+	if err != nil {
+		html.ServerError(w, r, err)
+		return
+	}
+
+	categories, err := h.store.Categories(user.ID)
+	if err != nil {
+		html.ServerError(w, r, err)
+		return
+	}
+
+	bookmarkletURL := request.QueryStringParam(r, "uri", "")
+
+	// Extract URL from text supplied by Web Share Target API.
+	//
+	// This is because Android intents have no concept of URL, so apps
+	// just shove a URL directly into the EXTRA_TEXT intent field.
+	//
+	// See https://bugs.chromium.org/p/chromium/issues/detail?id=789379.
+	text := request.QueryStringParam(r, "text", "")
+	if text != "" && bookmarkletURL == "" {
+		bookmarkletURL = xurls.Relaxed().FindString(text)
+	}
+
+	view.Set("form", form.SubscriptionForm{URL: bookmarkletURL})
+	view.Set("categories", categories)
+	view.Set("menu", "feeds")
+	view.Set("user", user)
+	view.Set("countUnread", h.store.CountUnreadEntries(user.ID))
+	view.Set("countErrorFeeds", h.store.CountUserFeedsWithErrors(user.ID))
+	view.Set("defaultUserAgent", config.Opts.HTTPClientUserAgent())
+	view.Set("hasProxyConfigured", config.Opts.HasHTTPClientProxyConfigured())
+
+	html.OK(w, r, view.Render("add_subscription"))
+}