Remove unused icons & styles (#28288)

* Remove stale _LegacyRoomHeader.pcss and icons

Signed-off-by: Michael Telatynski <[email protected]>

* Remove unused icons

Signed-off-by: Michael Telatynski <[email protected]>

* Ensure legacy header styles are not used by HTML export

Signed-off-by: Michael Telatynski <[email protected]>

---------

Signed-off-by: Michael Telatynski <[email protected]>

Author: t3chguy

playwright/snapshots/chat-export/html-export.spec.ts/html-export-linux.png

@@ -286,7 +286,6 @@
 @import "./views/rooms/_HistoryTile.pcss";
 @import "./views/rooms/_IRCLayout.pcss";
 @import "./views/rooms/_JumpToBottomButton.pcss";
-@import "./views/rooms/_LegacyRoomHeader.pcss";
 @import "./views/rooms/_LinkPreviewGroup.pcss";
 @import "./views/rooms/_LinkPreviewWidget.pcss";
 @import "./views/rooms/_LiveContentSummary.pcss";

res/css/_components.pcss

@@ -181,11 +181,6 @@ Please see LICENSE files in the repository root for full details.
     }
 }
 
-/* Rooms with immersive content */
-.mx_RoomView_immersive .mx_LegacyRoomHeader_wrapper {
-    border: unset;
-}
-
 .mx_RoomView_inCall {
     .mx_RoomView_statusAreaBox_line {
         margin-top: 2px;