Refine the colors of some more components (#12343)

* Refine the colors of some more components

This is a reintroduction of https://github.com/matrix-org/matrix-react-sdk/pull/12255, and should be the last part of the Compound color refinement work (https://github.com/element-hq/element-web/issues/26992). I've updated the following components to reflect design decisions (https://www.figma.com/file/pqhlirZFEwEp5XpudSbiia/Theming-Web-templates?type=design&node-id=80-60219&mode=design&t=mjqwylUie1vRwzOV-0) that will help them fit in better with the new design system:

- Message bubbles
- Pills
- Sent indicators
- Jump to bottom/unread buttons
- Composer placeholder
- Notification badges
- Room sublists
- Verification shields
- Date separators
- Tooltips

Closes https://github.com/element-hq/element-web/issues/22122

* Update some screenshots

res/themes/light-high-contrast/css/_light-high-contrast.pcss

@@ -31,7 +31,6 @@ $button-secondary-bg-color: $accent-fg-color;
 $message-action-bar-fg-color: $primary-content;
 $voice-record-stop-border-color: $quinary-content;
 $voice-record-icon-color: $tertiary-content;
-$eventbubble-reply-color: $quaternary-content;
 $roomtopic-color: $secondary-content;
 
 /**