fix(room): one width for every right-hand panel (#263)

Members and bookmarks were 266px, the gallery 320, the threads list 340,
a thread and widgets 360. Swapping panels resized the room view, so the
header icons slid sideways (74px for members -> threads) and a second
click on the same spot opened Widgets instead of closing the panel. All
six now use SIDE_PANEL_WIDTH (340px, styles/sidePanel.ts).

Fixes #263

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017PCb59uY3UKqDqt7B6hzd5

src/app/features/room/MediaGallery.css.ts

@@ -1,13 +1,13 @@
 import { style } from '@vanilla-extract/css';
 import { color, config, toRem } from 'folds';
+import { SIDE_PANEL_WIDTH } from '../../styles/sidePanel';
 
 // Right-side drawer DOCKED into the room layout row (a flex sibling of the
-// timeline), exactly like MembersDrawer — not a floating overlay. 320px is a
-// little wider than the 266px member/bookmark drawers because it hosts a media
-// grid. On narrow viewports it becomes a full-screen fixed panel, matching the
-// app's other drawers.
+// timeline), exactly like MembersDrawer — not a floating overlay. Same width as
+// every other right-hand panel (styles/sidePanel.ts, #263). On narrow viewports
+// it becomes a full-screen fixed panel, matching the app's other drawers.
 export const MediaGalleryDrawer = style({
-  width: toRem(320),
+  width: SIDE_PANEL_WIDTH,
   overflow: 'hidden',
   '@media': {
     '(max-width: 750px)': {

src/app/features/room/MembersDrawer.css.ts

@@ -1,8 +1,9 @@
 import { keyframes, style } from '@vanilla-extract/css';
-import { config, toRem } from 'folds';
+import { config } from 'folds';
+import { SIDE_PANEL_WIDTH } from '../../styles/sidePanel';
 
 export const MembersDrawer = style({
-  width: toRem(266),
+  width: SIDE_PANEL_WIDTH,
   '@media': {
     '(max-width: 750px)': {
       position: 'fixed',

src/app/features/room/thread/ThreadPanel.css.ts

@@ -1,8 +1,9 @@
 import { style } from '@vanilla-extract/css';
-import { config, toRem } from 'folds';
+import { config } from 'folds';
+import { SIDE_PANEL_WIDTH } from '../../../styles/sidePanel';
 
 export const ThreadPanel = style({
-  width: toRem(360),
+  width: SIDE_PANEL_WIDTH,
   '@media': {
     '(max-width: 750px)': {
       position: 'fixed',

src/app/features/room/thread/ThreadsListPanel.css.ts

@@ -1,8 +1,9 @@
 import { style } from '@vanilla-extract/css';
-import { color, config, toRem } from 'folds';
+import { color, config } from 'folds';
+import { SIDE_PANEL_WIDTH } from '../../../styles/sidePanel';
 
 export const ThreadsListPanel = style({
-  width: toRem(340),
+  width: SIDE_PANEL_WIDTH,
   '@media': {
     '(max-width: 750px)': {
       position: 'fixed',

src/app/features/room/widgets/WidgetsPanel.css.ts

@@ -1,8 +1,9 @@
 import { style } from '@vanilla-extract/css';
-import { config, toRem } from 'folds';
+import { config } from 'folds';
+import { SIDE_PANEL_WIDTH } from '../../../styles/sidePanel';
 
 export const WidgetsPanel = style({
-  width: toRem(360),
+  width: SIDE_PANEL_WIDTH,
   '@media': {
     '(max-width: 750px)': {
       position: 'fixed',