Improve timeline scroll, media layout, avatars, and emoji coverage.

Remember room scroll position across switches, reserve image/video heights from Matrix dimensions, cache authenticated media blobs for avatars, restore jumbo emoji-only messages, and extend emoji font unicode-range for Unicode 15 glyphs.

src/app/components/message/layout/layout.css.ts

@@ -1,4 +1,5 @@
-import { createVar, keyframes, style, styleVariants } from '@vanilla-extract/css';
+import { createVar, globalStyle, keyframes, style, styleVariants } from '@vanilla-extract/css';
+import * as htmlCss from '../../../styles/CustomHtml.css';
 import { recipe, RecipeVariants } from '@vanilla-extract/recipes';
 import { DefaultReset, color, config, toRem } from 'folds';
 
@@ -117,6 +118,7 @@ export const MessageBase = recipe({
     collapse: {
       true: {
         marginTop: 0,
+        paddingTop: config.space.S0,
       },
     },
     autoCollapse: {
@@ -209,6 +211,8 @@ export const UsernameBold = style({
   fontWeight: 550,
 });
 
+const jumboEmojiSize = toRem(70);
+
 export const MessageTextBody = recipe({
   base: {
     wordBreak: 'break-word',
@@ -226,8 +230,9 @@ export const MessageTextBody = recipe({
     },
     jumboEmoji: {
       true: {
-        fontSize: '1.504em',
-        lineHeight: '1.4962em',
+        lineHeight: 1,
+        overflow: 'visible',
+        overflowY: 'visible',
       },
     },
     emote: {
@@ -240,3 +245,29 @@ export const MessageTextBody = recipe({
 });
 
 export type MessageTextBodyVariants = RecipeVariants<typeof MessageTextBody>;
+
+const jumboEmojiClass = MessageTextBody.classNames.variants.jumboEmoji.true;
+
+globalStyle(`${jumboEmojiClass} .${htmlCss.EmoticonBase}`, {
+  height: jumboEmojiSize,
+  padding: 0,
+  overflow: 'visible',
+  verticalAlign: 'middle',
+});
+
+globalStyle(`${jumboEmojiClass} .${htmlCss.Emoticon.classNames.base}`, {
+  fontSize: jumboEmojiSize,
+  height: jumboEmojiSize,
+  minWidth: jumboEmojiSize,
+  lineHeight: 1,
+  position: 'static',
+  top: 0,
+  overflow: 'visible',
+});
+
+globalStyle(`${jumboEmojiClass} .${htmlCss.EmoticonImg}`, {
+  height: jumboEmojiSize,
+  width: jumboEmojiSize,
+  maxHeight: 'none',
+  objectFit: 'contain',
+});