Message Pinning: rework the message pinning list in the right panel (#12825)

* Fix pinning event loading after restart

* Update deps

* Replace pinned event list

* Add a dialog to confirm to unpin all messages

* Use `EmptyState` when there is no pinned messages

* Rework `PinnedEventTile` tests

* Add comments and refactor `PinnedMessageCard`

* Rework `PinnedMessageCard` tests

* Add tests for `UnpinAllDialog`

* Add e2e tests for pinned messages

* Replace 3px custom gap by 4px gap

* Use string interpolation for `Pin` action.

* Update playright sceenshot for empty state

src/components/views/dialogs/UnpinAllDialog.tsx

@@ -0,0 +1,77 @@
+/*
+ * Copyright 2024 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 React, { JSX } from "react";
+import { Button, Text } from "@vector-im/compound-web";
+import { EventType, MatrixClient } from "matrix-js-sdk/src/matrix";
+import { logger } from "matrix-js-sdk/src/logger";
+
+import BaseDialog from "../dialogs/BaseDialog";
+import { _t } from "../../../languageHandler";
+
+/**
+ * Properties for {@link UnpinAllDialog}.
+ */
+interface UnpinAllDialogProps {
+    /*
+     * The matrix client to use.
+     */
+    matrixClient: MatrixClient;
+    /*
+     * The room ID to unpin all events in.
+     */
+    roomId: string;
+    /*
+     * Callback for when the dialog is closed.
+     */
+    onFinished: () => void;
+}
+
+/**
+ * A dialog that asks the user to confirm unpinning all events in a room.
+ */
+export function UnpinAllDialog({ matrixClient, roomId, onFinished }: UnpinAllDialogProps): JSX.Element {
+    return (
+        <BaseDialog
+            hasCancel={true}
+            title={_t("right_panel|pinned_messages|unpin_all|title")}
+            titleClass="mx_UnpinAllDialog_title"
+            className="mx_UnpinAllDialog"
+            onFinished={onFinished}
+            fixedWidth={false}
+        >
+            <Text as="span">{_t("right_panel|pinned_messages|unpin_all|content")}</Text>
+            <div className="mx_UnpinAllDialog_buttons">
+                <Button
+                    destructive={true}
+                    onClick={async () => {
+                        try {
+                            await matrixClient.sendStateEvent(roomId, EventType.RoomPinnedEvents, { pinned: [] }, "");
+                        } catch (e) {
+                            logger.error("Failed to unpin all events:", e);
+                        }
+                        onFinished();
+                    }}
+                >
+                    {_t("action|continue")}
+                </Button>
+                <Button kind="tertiary" onClick={onFinished}>
+                    {_t("action|cancel")}
+                </Button>
+            </div>
+        </BaseDialog>
+    );
+}