Delete groups (legacy communities system) (#8027)

* Remove deprecated feature_communities_v2_prototypes

* Update _components

* i18n

* delint

* Cut out a bit more dead code

* Carve into legacy components

* Carve into mostly the room list code

* Carve into instances of "groupId"

* Carve out more of what comes up with "groups"

* Carve out some settings

* ignore related groups state

* Remove instances of spacesEnabled

* Fix some obvious issues

* Remove now-unused css

* Fix variable naming for legacy components

* Update i18n

* Misc cleanup from manual review

* Update snapshot for changed flag

* Appease linters

* rethemedex

* Remove now-unused AddressPickerDialog

* Make ConfirmUserActionDialog's member a required prop

* Remove useless override from RightPanelStore

* Remove extraneous CSS

* Update i18n

* Demo: "Communities are now Spaces" landing page

* Restore linkify for group IDs

* Demo: Dialog on click for communities->spaces notice

* i18n for demos

* i18n post-merge

* Update copy

* Appease the linter

* Post-merge cleanup

* Re-add spaces_learn_more_url to the new SdkConfig place

* Round 1 of post-merge fixes

* i18n

Co-authored-by: Michael Telatynski <7t3chguy@gmail.com>

src/group_helpers.tsx

@@ -0,0 +1,45 @@
+/*
+Copyright 2022 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import * as React from "react";
+
+import Modal from "./Modal";
+import QuestionDialog from "./components/views/dialogs/QuestionDialog";
+import { _t } from "./languageHandler";
+import SdkConfig, { DEFAULTS } from "./SdkConfig";
+
+export function showGroupReplacedWithSpacesDialog(groupId: string) {
+    const learnMoreUrl = SdkConfig.get().spaces_learn_more_url ?? DEFAULTS.spaces_learn_more_url;
+    Modal.createTrackedDialog("Groups are now Spaces", '', QuestionDialog, {
+        title: _t("That link is no longer supported"),
+        description: <>
+            <p>
+                { _t(
+                    "You're trying to access a community link (%(groupId)s).<br/>" +
+                        "Communities are no longer supported and have been replaced by spaces.<br2/>" +
+                        "<a>Learn more about spaces here.</a>",
+                    { groupId },
+                    {
+                        br: () => <br />,
+                        br2: () => <br />,
+                        a: (sub) => <a href={learnMoreUrl} rel="noreferrer noopener" target="_blank">{ sub }</a>,
+                    },
+                ) }
+            </p>
+        </>,
+        hasCancelButton: false,
+    });
+}