fix(ui): resolve 29 native UI/UX inconsistencies from folds design audit

Fixes N1–N94 findings from LOTUS_BUGS.md audit pass. Key changes:

- ProfileDecoration: raw <button> → folds <Button> for save/remove; remove
  undefined --accent-cyan var
- UserRoomProfile: textarea border uses color.SurfaceVariant.ContainerLine
  and config tokens instead of undefined --border-interactive var
- LotusToastContainer: z-index raised from 9997 → 10001 so toasts appear
  above Night Light overlay (9998) and modals (9999)
- Message.tsx: DeliveryStatus replaces Unicode glyphs with Icon components;
  MessageQuickReactions returns null instead of <span />; forward menu item
  gets correct size="100" on after icon
- AudioContent: speed chip variant/radii now matches Play chip (Secondary/300)
- ReadReceiptAvatars: pill border/radius/padding → folds config tokens;
  remove dead receipt-pill-btn className
- EventReaders: Header size 600→500; close button gets radii="300";
  borderBottom shorthand → borderBottomWidth token; remove raw fontSize
- General.tsx: selected background/seasonal picker border uses
  color.Primary.Main instead of color.Critical.Main (error red)
- RoomInsights: SectionHeader drops textTransform/letterSpacing/opacity;
  chart borderRadius → config tokens; remove raw fontSize:9;
  warning banner → SequenceCard
- RoomProfile.tsx: formatting toolbar raw <button> → folds <Button>;
  topic read-mode renders formatted_body via sanitizeCustomHtml
- MsgTypeRenderers: location Open button Chip→Button; opacity:0.65→priority
- UploadCardRenderer: caption raw <input> → folds <Input>
- VoiceMessageRecorder: replace undefined --bg-surface-variant/--tc-*
  vars with color.* tokens; replace bare <audio controls> with
  IconButton play/pause toggle
- App.tsx: mention highlight uses WCAG 2.1 relative luminance (gamma
  linearization) instead of simplified approximation; border now rgba
  semi-transparent instead of same color as background
- RoomNavItem: Mute MenuItem icon moved to before prop
- SearchFilters: HasLink chip variant="Success" outlined to match filter bar
- RoomViewHeader: Server Notice chip radii Pill→300; fix jotai import order
- Fix ESLint import/order errors in DeviceVerificationSetup, RoomTopicViewer,
  MediaGallery, and RoomViewHeader

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/app/features/settings/general/General.tsx

@@ -1658,7 +1658,7 @@ function SeasonalBgGrid({
                 borderRadius: toRem(8),
                 cursor: 'pointer',
                 border: selected
-                  ? `2px solid ${color.Critical.Main}`
+                  ? `2px solid ${color.Primary.Main}`
                   : '2px solid rgba(128,128,128,0.25)',
                 padding: 0,
                 overflow: 'hidden',
@@ -1687,7 +1687,7 @@ function SeasonalBgGrid({
                 )}
               </div>
             </button>
-            <Text size="T200" style={selected ? { color: color.Critical.Main } : undefined}>
+            <Text size="T200" style={selected ? { color: color.Primary.Main } : undefined}>
               {opt.label}
             </Text>
           </Box>
@@ -1724,7 +1724,7 @@ function ChatBgGrid() {
               cursor: 'pointer',
               border:
                 chatBackground === opt.value
-                  ? `2px solid ${color.Critical.Main}`
+                  ? `2px solid ${color.Primary.Main}`
                   : '2px solid rgba(128,128,128,0.25)',
               padding: 0,
               overflow: 'hidden',
@@ -1733,7 +1733,7 @@ function ChatBgGrid() {
           />
           <Text
             size="T200"
-            style={chatBackground === opt.value ? { color: color.Critical.Main } : undefined}
+            style={chatBackground === opt.value ? { color: color.Primary.Main } : undefined}
           >
             {opt.label}
           </Text>