feat(room): give the 1:1 peer name its own dark chip matching the message bubble and round both with a minimal all-corners radius

src/app/components/message/layout/Stream.tsx

@@ -225,7 +225,12 @@ export const StreamLayout = as<'div', StreamLayoutProps>(
         </span>
         <div className={css.StreamColumn}>
           {header && (
-            <div className={css.StreamName} ref={headerRef}>
+            <div
+              // Peer (incoming) names render in a chip the same dark surface as
+              // their message bubble; own names stay plain (own = plain text).
+              className={classNames(css.StreamName, !isOwn && css.StreamNamePeerBubble)}
+              ref={headerRef}
+            >
               {header}
             </div>
           )}

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

@@ -191,6 +191,9 @@ const StreamSyslineDotSize = toRem(6);
 const StreamDayDotSize = toRem(12.1);
 const StreamRailLineWidth = '1px';
 const StreamBubbleBorderWidth = '1px';
+// Minimal, all-corners rounding for the incoming bubble + the peer name chip
+// (user request — like the VS Code reference, no sharp/notched corner).
+const StreamBubbleRadius = toRem(6);
 const StreamTimeLineHeight = toRem(13);
 const StreamRailBridgeY = config.space.S400;
 
@@ -199,7 +202,10 @@ const StreamRailBridgeY = config.space.S400;
 // larger than chat body (T400 = 15px). The dot + timestamp vertically centre
 // on this line, so its line-height drives the rail geometry below.
 const StreamNameFontSize = toRem(16);
-const StreamNameLineHeight = toRem(20);
+// Line-height (not font) drives the name-chip height: 26.4px (20 × 1.2 × 1.1)
+// gives the peer name bubble more vertical breathing room around the 16px nick
+// while the dot + timestamp follow automatically via StreamHeaderInnerCenterY.
+const StreamNameLineHeight = toRem(26.4);
 
 // Vertical centre of the author-name line, measured from the row's
 // content-area top. The name is now the FIRST child of StreamColumn (track 3)
@@ -444,13 +450,13 @@ export const StreamBubble = recipe({
     // Incoming (peer) bubble — filled with the SAME surface as the composer
     // card (`color.Surface.Container`, see RoomView.css.ts) so the bubble and
     // the input form read as one material; it sits a step darker than the
-    // `SurfaceVariant.Container` page background. Top-left corner flat, other
+    // `SurfaceVariant.Container` page background. Minimal rounding on ALL four
-    // three rounded (user point 7). Own messages override to a no-chrome
+    // corners (no sharp/notched corner). Own messages override to a no-chrome
     // plain block below.
     backgroundColor: color.Surface.Container,
     color: color.SurfaceVariant.OnContainer,
     border: `${StreamBubbleBorderWidth} solid ${color.Surface.ContainerLine}`,
-    borderRadius: `${toRem(4)} ${toRem(16)} ${toRem(16)} ${toRem(16)}`,
+    borderRadius: StreamBubbleRadius,
     // Padding bumped ~1.1× (user request) so the bubble reads a touch larger
     // around the text: vertical 8→8.8px, horizontal 15→16.5px.
     paddingTop: toRem(8.8),
@@ -571,6 +577,21 @@ globalStyle(`${StreamName} > *`, {
   minWidth: 0,
 });
 
+// Peer (incoming) author name rendered as a chip in the SAME surface as the
+// message bubble (`color.Surface.Container`) — a mini incoming-bubble for the
+// label, with the same minimal all-corners rounding (user request). Own names
+// stay plain (own messages are plain text). Horizontal padding only — NO
+// vertical padding, so the name's line box (and the dot/timestamp aligned to
+// its centre) doesn't shift; the fill spans the line height.
+export const StreamNamePeerBubble = style({
+  backgroundColor: color.Surface.Container,
+  // Slightly larger rounding than the message bubble (user request) + wider
+  // horizontal padding to match the taller chip.
+  borderRadius: toRem(9),
+  paddingLeft: toRem(11),
+  paddingRight: toRem(11),
+});
+
 // Message-row timestamp — grid item in track 1, content-sized. Pushed
 // down by the same Y as StreamHeaderDotHalo so timestamp / dot / Username
 // share one baseline.