feat: human-friendly session titles in header and sidebar

Replace raw session keys/UUIDs with readable names derived from
session metadata (label, kind, channel). Priority: label > kind-based
name (Main, Cron, Task) with channel suffix > cleaned key fallback.

New utility: src/lib/sessionName.ts used by both Header and Sidebar.

src/components/Header.tsx

@@ -2,6 +2,7 @@ import { Menu, Sparkles, LogOut, Volume2, VolumeOff, Cpu } from 'lucide-react';
 import type { ConnectionStatus, Session } from '../types';
 import { useT } from '../hooks/useLocale';
 import { LanguageSelector } from './LanguageSelector';
+import { sessionDisplayName } from '../lib/sessionName';
 
 interface Props {
   status: ConnectionStatus;
@@ -15,7 +16,7 @@ interface Props {
 
 export function Header({ status, sessionKey, onToggleSidebar, activeSessionData, onLogout, soundEnabled, onToggleSound }: Props) {
   const t = useT();
-  const sessionLabel = sessionKey.split(':').pop() || sessionKey;
+  const sessionLabel = activeSessionData ? sessionDisplayName(activeSessionData) : (sessionKey.split(':').pop() || sessionKey);
 
   return (
     <>

src/components/Sidebar.tsx

@@ -3,6 +3,7 @@ import { X, Sparkles, Search, Pin, Trash2 } from 'lucide-react';
 import type { Session } from '../types';
 import { useT } from '../hooks/useLocale';
 import { SessionIcon } from './SessionIcon';
+import { sessionDisplayName } from '../lib/sessionName';
 
 const PINNED_KEY = 'pinchchat-pinned-sessions';
 const WIDTH_KEY = 'pinchchat-sidebar-width';
@@ -125,7 +126,7 @@ export function Sidebar({ sessions, activeSession, onSwitch, onDelete, open, onC
     let list = sessions;
     if (filter.trim()) {
       const q = filter.toLowerCase();
-      list = sessions.filter(s => (s.label || s.key).toLowerCase().includes(q));
+      list = sessions.filter(s => sessionDisplayName(s).toLowerCase().includes(q));
     }
     // Sort pinned sessions to top (preserving relative order within each group)
     const pinnedList = list.filter(s => pinned.has(s.key));
@@ -249,7 +250,7 @@ export function Sidebar({ sessions, activeSession, onSwitch, onDelete, open, onC
                   </div>
                   <div className="flex-1 min-w-0">
                     <div className="flex items-center gap-1">
-                      <span className="flex-1 truncate">{s.label || s.key}</span>
+                      <span className="flex-1 truncate">{sessionDisplayName(s)}</span>
                       <button
                         onClick={(e) => togglePin(s.key, e)}
                         className={`shrink-0 p-0.5 rounded-lg transition-all ${

src/lib/sessionName.ts

@@ -0,0 +1,49 @@
+import type { Session } from '../types';
+
+/**
+ * Derive a human-friendly display name for a session.
+ *
+ * Priority:
+ * 1. label (if set, e.g. sub-agent labels)
+ * 2. "Main" for kind=main
+ * 3. Kind + channel (e.g. "Cron · telegram")
+ * 4. Channel name capitalized
+ * 5. Cleaned session key (strip agent:xxx: prefix, truncate UUIDs)
+ */
+export function sessionDisplayName(session: Session): string {
+  if (session.label) return session.label;
+
+  const kind = session.kind;
+  const channel = session.channel;
+
+  if (kind === 'main') {
+    return channel ? `Main · ${capitalize(channel)}` : 'Main';
+  }
+
+  if (kind === 'cron') {
+    return channel ? `Cron · ${capitalize(channel)}` : 'Cron';
+  }
+
+  if (kind === 'isolated') {
+    return channel ? `Task · ${capitalize(channel)}` : 'Task';
+  }
+
+  if (channel) return capitalize(channel);
+
+  // Fallback: clean the session key
+  return cleanSessionKey(session.key);
+}
+
+function capitalize(s: string): string {
+  return s.charAt(0).toUpperCase() + s.slice(1);
+}
+
+function cleanSessionKey(key: string): string {
+  // Strip "agent:<id>:" prefix
+  const stripped = key.replace(/^agent:[^:]+:/, '');
+  // If it looks like a UUID, show first 8 chars
+  if (/^[0-9a-f]{8}-[0-9a-f]{4}-/.test(stripped)) {
+    return stripped.slice(0, 8) + '…';
+  }
+  return stripped;
+}