Add Shared Media drawer and harden same-room navigation.

Widen the media panel, support skinny full-page mode, keep jump-to-latest and return-to-previous reliable, and stop same-room event jumps from remounting the outlet or yanking the sidebar.

src/app/features/room/room-media-menu/RoomMediaMenu.css.ts

@@ -0,0 +1,149 @@
+import { style } from '@vanilla-extract/css';
+import { color, config, toRem } from 'folds';
+
+export const MediaDrawer = style({
+  width: toRem(399),
+});
+
+export const MediaDrawerSolo = style({
+  width: '100%',
+  flexGrow: 1,
+});
+
+export const MediaDrawerHeader = style({
+  flexShrink: 0,
+  padding: `0 ${config.space.S200} 0 ${config.space.S300}`,
+  borderBottomWidth: config.borderWidth.B300,
+});
+
+export const MediaDrawerContentBase = style({
+  position: 'relative',
+  overflow: 'hidden',
+});
+
+export const MediaDrawerContent = style({
+  padding: `${config.space.S100} ${config.space.S200} ${config.space.S200}`,
+});
+
+export const MediaMonthSection = style({
+  marginBottom: config.space.S300,
+});
+
+export const MediaMonthHeader = style({
+  position: 'sticky',
+  top: 0,
+  zIndex: 2,
+  margin: '5px 0',
+  padding: `0 ${config.space.S100}`,
+  lineHeight: 1.2,
+  backgroundColor: color.Background.Container,
+  color: color.Background.OnContainer,
+});
+
+export const MediaDaySection = style({
+  marginBottom: config.space.S300,
+});
+
+export const MediaDayHeader = style({
+  padding: `${config.space.S100} ${config.space.S100} ${config.space.S200}`,
+  color: color.Background.OnContainer,
+});
+
+export const MediaGrid = style({
+  display: 'grid',
+  gridTemplateColumns: 'repeat(3, minmax(0, 1fr))',
+  gap: config.space.S200,
+});
+
+export const MediaTile = style({
+  position: 'relative',
+  aspectRatio: '1',
+  borderRadius: config.radii.R400,
+  overflow: 'hidden',
+  border: 'none',
+  padding: 0,
+  cursor: 'pointer',
+  backgroundColor: color.SurfaceVariant.Container,
+  color: color.SurfaceVariant.OnContainer,
+});
+
+export const MediaTileImg = style({
+  width: '100%',
+  height: '100%',
+  objectFit: 'cover',
+  display: 'block',
+});
+
+export const MediaTileBadge = style({
+  position: 'absolute',
+  right: config.space.S100,
+  bottom: config.space.S100,
+  display: 'flex',
+  alignItems: 'center',
+  justifyContent: 'center',
+  width: toRem(24),
+  height: toRem(24),
+  borderRadius: config.radii.R400,
+  backgroundColor: 'rgba(0, 0, 0, 0.55)',
+  color: '#fff',
+});
+
+export const MediaEmpty = style({
+  padding: config.space.S400,
+  textAlign: 'center',
+});
+
+export const MediaFooter = style({
+  padding: config.space.S200,
+  display: 'flex',
+  justifyContent: 'center',
+});
+
+export const MediaUserFiltersScroll = style({
+  flexShrink: 0,
+  flexGrow: 0,
+  overflowX: 'auto',
+  overflowY: 'hidden',
+  scrollbarWidth: 'thin',
+  scrollbarColor: `${color.SurfaceVariant.ContainerLine} ${color.SurfaceVariant.Container}`,
+  selectors: {
+    '&::-webkit-scrollbar': {
+      height: toRem(8),
+    },
+    '&::-webkit-scrollbar-track': {
+      backgroundColor: color.SurfaceVariant.Container,
+      borderRadius: config.radii.R400,
+    },
+    '&::-webkit-scrollbar-thumb': {
+      backgroundColor: color.SurfaceVariant.ContainerLine,
+      borderRadius: config.radii.R400,
+      border: `${config.borderWidth.B300} solid ${color.SurfaceVariant.Container}`,
+      backgroundClip: 'padding-box',
+    },
+    '&::-webkit-scrollbar-thumb:hover': {
+      backgroundColor: color.Surface.ContainerLine,
+    },
+  },
+});
+
+export const MediaUserFilters = style({
+  display: 'flex',
+  flexWrap: 'nowrap',
+  alignItems: 'center',
+  gap: config.space.S500,
+  padding: `${config.space.S200} ${config.space.S200}`,
+  width: 'max-content',
+  minWidth: '100%',
+  boxSizing: 'border-box',
+});
+
+export const MediaUserChip = style({
+  flexShrink: 0,
+});
+
+export const MediaUserChipLabel = style({
+  maxWidth: toRem(72),
+  overflow: 'hidden',
+  textOverflow: 'ellipsis',
+  whiteSpace: 'nowrap',
+});