feat(ui): phone-style layout for direct calls

The call screen now shows two different layouts depending on
whether the call is a 1:1 direct call or a room/group call:

**Direct call (directCallPeer set):**
- Large centered identicon (96px circular with glow)
- Peer name (22px bold) + fingerprint (11px mono)
- Connection badge: "P2P Direct" (green), "Via Relay" (blue),
  or "Connecting..." (yellow) — auto-detected from the
  call-debug buffer's dual_path_race_won event
- Room name header shows the peer's alias/fp instead of "general"
- Group participant list is hidden

**Room/group call (directCallPeer null):**
- Existing group participant list layout — unchanged

The badge updates live from pollStatus by scanning the debug
buffer for the connect:dual_path_race_won event. If the path
was "Direct" → green P2P badge; if "Relay" → blue relay badge.
Before the race resolves, shows yellow "Connecting...".

directCallView is cleared on showConnectScreen (call end).

CSS in style.css: .direct-call-view, .dc-identicon, .dc-name,
.dc-fp, .dc-badge with .relay and .connecting modifiers.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

desktop/index.html

@@ -111,6 +111,16 @@
         <div class="level-meter">
           <div id="level-bar" class="level-bar-fill"></div>
         </div>
+        <!-- Direct-call phone layout — shown instead of the group
+             participant list when directCallPeer is set. Centered
+             identicon, name, fp, connection badge. Hidden for
+             room calls (directCallPeer == null). -->
+        <div id="direct-call-view" class="direct-call-view hidden">
+          <div id="dc-identicon" class="dc-identicon"></div>
+          <div id="dc-name" class="dc-name">Unknown</div>
+          <div id="dc-fp" class="dc-fp"></div>
+          <div id="dc-badge" class="dc-badge">Connecting...</div>
+        </div>
         <div id="participants" class="participants"></div>
         <div class="controls">
           <button id="mic-btn" class="control-btn" title="Toggle Mic (m)">

desktop/src/main.ts

@@ -169,6 +169,11 @@ const callTimer = document.getElementById("call-timer")!;
 const callStatus = document.getElementById("call-status")!;
 const levelBar = document.getElementById("level-bar")!;
 const participantsDiv = document.getElementById("participants")!;
+const directCallView = document.getElementById("direct-call-view")!;
+const dcIdenticon = document.getElementById("dc-identicon")!;
+const dcName = document.getElementById("dc-name")!;
+const dcFp = document.getElementById("dc-fp")!;
+const dcBadge = document.getElementById("dc-badge")!;
 const micBtn = document.getElementById("mic-btn")!;
 const micIcon = document.getElementById("mic-icon")!;
 const spkBtn = document.getElementById("spk-btn")!;
@@ -846,7 +851,25 @@ let directCallPeer: { fingerprint: string; alias: string | null } | null = null;
 function showCallScreen() {
   connectScreen.classList.add("hidden");
   callScreen.classList.remove("hidden");
-  roomName.textContent = roomInput.value;
+
+  // Direct call → phone-style layout; room call → group layout.
+  if (directCallPeer) {
+    const fp = directCallPeer.fingerprint || "";
+    const alias = directCallPeer.alias;
+    roomName.textContent = alias || fp.substring(0, 16) || "Direct Call";
+    dcName.textContent = alias || "Unknown";
+    dcFp.textContent = fp;
+    dcIdenticon.innerHTML = "";
+    dcIdenticon.appendChild(createIdenticonEl(fp || "?", 96, true));
+    dcBadge.textContent = "Connecting...";
+    dcBadge.className = "dc-badge connecting";
+    directCallView.classList.remove("hidden");
+    participantsDiv.classList.add("hidden");
+  } else {
+    roomName.textContent = roomInput.value;
+    directCallView.classList.add("hidden");
+    participantsDiv.classList.remove("hidden");
+  }
   callStatus.className = "status-dot";
   statusInterval = window.setInterval(pollStatus, 250);
   // Sync the Speaker/Earpiece label with the OS state (Android only; on
@@ -984,23 +1007,38 @@ async function pollStatus() {
     const pct = rms > 0 ? Math.min(100, (Math.log(rms) / Math.log(32767)) * 100) : 0;
     levelBar.style.width = `${pct}%`;
 
-    // Participants grouped by relay. For direct P2P calls the
-    // relay never sends a RoomUpdate (neither peer joins the
-    // relay's media room) so st.participants is empty. If we
-    // have a directCallPeer from the signal plane, inject a
-    // synthetic entry so the UI shows who we're talking to.
-    const displayParticipants =
-      st.participants.length === 0 && directCallPeer
-        ? [{ ...directCallPeer, relay_label: "P2P Direct" }]
-        : st.participants;
+    // Direct-call phone-style layout: update the connection
+    // badge from the call-debug buffer or from participants.
+    if (directCallPeer) {
+      // Check the debug buffer for the race result to label
+      // the connection type (P2P Direct vs Relay).
+      const raceWon = callDebugBuffer.find((e) => e.step === "connect:dual_path_race_won");
+      const engineOk = callDebugBuffer.find((e) => e.step === "connect:call_engine_started");
+      if (engineOk) {
+        if (raceWon?.details?.path === "Direct") {
+          dcBadge.textContent = "P2P Direct";
+          dcBadge.className = "dc-badge";
+        } else {
+          dcBadge.textContent = "Via Relay";
+          dcBadge.className = "dc-badge relay";
+        }
+      }
+      // Skip the group participant rendering — direct-call
+      // view is already visible and showing the peer.
+    }
 
-    if (displayParticipants.length === 0) {
+    // Participants grouped by relay (group/room calls only).
+    // Hidden when directCallPeer is set — the phone-style
+    // layout above handles the 1:1 display.
+    if (directCallPeer) {
+      // no-op: direct call view handles it
+    } else if (st.participants.length === 0) {
       participantsDiv.innerHTML = '<div class="participants-empty">Waiting for participants...</div>';
     } else {
       participantsDiv.innerHTML = "";
       // Group by relay_label (null = this relay)
       const groups: Record<string, typeof st.participants> = {};
-      displayParticipants.forEach((p: any) => {
+      st.participants.forEach((p: any) => {
         const relay = p.relay_label || "This Relay";
         if (!groups[relay]) groups[relay] = [];
         groups[relay].push(p);

desktop/src/style.css

@@ -371,7 +371,65 @@ button.primary:disabled { opacity: 0.5; cursor: not-allowed; }
   transition: width 0.1s ease-out;
 }
 
-/* ── Participants ── */
+/* ── Direct call phone-style layout ── */
+.direct-call-view {
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  justify-content: center;
+  flex: 1;
+  padding: 32px 16px;
+  gap: 8px;
+}
+.dc-identicon {
+  width: 96px;
+  height: 96px;
+  border-radius: 50%;
+  overflow: hidden;
+  margin-bottom: 12px;
+  box-shadow: 0 0 24px rgba(74, 222, 128, 0.15);
+}
+.dc-identicon canvas,
+.dc-identicon svg,
+.dc-identicon img {
+  width: 100% !important;
+  height: 100% !important;
+  display: block;
+}
+.dc-name {
+  font-size: 22px;
+  font-weight: 600;
+  color: var(--text);
+  text-align: center;
+}
+.dc-fp {
+  font-size: 11px;
+  font-family: ui-monospace, Menlo, Monaco, 'Courier New', monospace;
+  color: var(--text-dim);
+  text-align: center;
+  word-break: break-all;
+  max-width: 280px;
+}
+.dc-badge {
+  display: inline-block;
+  margin-top: 8px;
+  padding: 4px 12px;
+  border-radius: 12px;
+  font-size: 11px;
+  font-weight: 500;
+  background: rgba(74, 222, 128, 0.12);
+  color: var(--green);
+}
+.dc-badge.relay {
+  background: rgba(96, 165, 250, 0.12);
+  color: #60a5fa;
+}
+.dc-badge.connecting {
+  background: rgba(250, 204, 21, 0.12);
+  color: var(--yellow);
+}
+
+/* ── Participants (group call layout) ── */
 .participants {
   background: var(--surface);
   border-radius: var(--radius);