Add link creation to rich text editor (#9775)

Add link creation to RTE

res/css/_components.pcss

@@ -308,6 +308,7 @@
 @import "./views/rooms/wysiwyg_composer/_SendWysiwygComposer.pcss";
 @import "./views/rooms/wysiwyg_composer/components/_Editor.pcss";
 @import "./views/rooms/wysiwyg_composer/components/_FormattingButtons.pcss";
+@import "./views/rooms/wysiwyg_composer/components/_LinkModal.pcss";
 @import "./views/settings/_AvatarSetting.pcss";
 @import "./views/settings/_CrossSigningPanel.pcss";
 @import "./views/settings/_CryptographyPanel.pcss";

res/css/views/rooms/wysiwyg_composer/components/_LinkModal.pcss

@@ -0,0 +1,29 @@
+/*
+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.
+*/
+
+.mx_LinkModal {
+    padding: $spacing-32;
+
+    .mx_Dialog_content {
+        margin-top: 30px;
+        margin-bottom: 42px;
+    }
+
+    .mx_LinkModal_content {
+        display: flex;
+        flex-direction: column;
+    }
+}

res/img/element-icons/room/composer/link.svg

@@ -0,0 +1,3 @@
+<svg width="16" height="16" viewBox="0 0 16 16" fill="none" xmlns="http://www.w3.org/2000/svg">
+<path d="M8.37751 4.10063L8.73382 3.74433C9.718 2.76019 11.3042 2.75074 12.2767 3.72324C13.2493 4.69573 13.2398 6.2819 12.2556 7.26605L10.5627 8.9589C9.57856 9.94304 7.99234 9.95249 7.01981 8.98M7.62266 11.8992L7.26619 12.2557C6.28201 13.2398 4.69578 13.2493 3.72325 12.2768C2.75073 11.3043 2.76018 9.7181 3.74436 8.73395L5.43717 7.0412C6.42134 6.05706 8.00756 6.04761 8.98009 7.0201" stroke="currentColor" stroke-width="1.5" stroke-linecap="round"/>
+</svg>