chat client fixes

packages/chat-client/src/components/ChatWindow.jsx

@@ -1,7 +1,18 @@
 import React, { useEffect, useRef } from 'react';
 import MessageBubble from './MessageBubble';
 
-export default function ChatWindow({ messages, loadingHistory, streaming, onSendMessage, onCancel, activeSession, onTogglePanel }) {
+export default function ChatWindow({
+  messages,
+  loadingHistory,
+  streaming,
+  onSendMessage,
+  onCancel,
+  activeSession,
+  onTogglePanel,
+  onBack,
+  canGoBack,
+  loadedModel,
+}) {
   const bottomRef = useRef(null);
   const inputRef = useRef(null);
   const [input, setInput] = React.useState('');
@@ -24,15 +35,59 @@ export default function ChatWindow({ messages, loadingHistory, streaming, onSend
     }
   }
 
+  // Trim .gguf for display
+  const modelLabel = loadedModel ? loadedModel.replace('.gguf', '') : null;
+
   return (
     <div className="flex-col flex-1 overflow-hidden" style={{ background: 'var(--bg-base)' }}>
 
       {/* Header */}
-      <div className="panel-header" style={{ padding: '0 12px 0 20px', justifyContent: 'space-between' }}>
-        <span className="text-base text-secondary">
-          {activeSession ? (activeSession.name || activeSession.external_id) : 'No session selected'}
-        </span>
-        <button className="btn-icon" onClick={onTogglePanel} title="Session info">⊹</button>
+      <div className="panel-header" style={{ padding: '0 12px 0 8px', justifyContent: 'space-between' }}>
+        <div style={{ display: 'flex', alignItems: 'center', gap: '4px', minWidth: 0 }}>
+          {/* Back button */}
+          {canGoBack && (
+            <button
+              className="btn-icon"
+              onClick={onBack}
+              title="Go back"
+              style={{ flexShrink: 0, fontSize: '16px', padding: '4px 8px' }}
+            >←</button>
+          )}
+          {/* Session name */}
+          <span className="text-base text-secondary truncate">
+            {activeSession ? (activeSession.name || activeSession.external_id) : 'New chat'}
+          </span>
+        </div>
+
+        <div style={{ display: 'flex', alignItems: 'center', gap: '8px', flexShrink: 0 }}>
+          {/* Loaded model pill */}
+          {modelLabel && (
+            <span style={{
+              fontSize: '11px',
+              color: 'var(--text-muted)',
+              background: 'var(--bg-elevated)',
+              border: '1px solid var(--border)',
+              borderRadius: '999px',
+              padding: '2px 10px',
+              maxWidth: '200px',
+              overflow: 'hidden',
+              textOverflow: 'ellipsis',
+              whiteSpace: 'nowrap',
+            }}>
+              {modelLabel}
+            </span>
+          )}
+          {!modelLabel && (
+            <span style={{
+              fontSize: '11px',
+              color: 'var(--text-muted)',
+              fontStyle: 'italic',
+            }}>
+              No model loaded
+            </span>
+          )}
+          <button className="btn-icon" onClick={onTogglePanel} title="Session info">⊹</button>
+        </div>
       </div>
 
       {/* Message thread */}
@@ -44,7 +99,7 @@ export default function ChatWindow({ messages, loadingHistory, streaming, onSend
             gap: '12px',
           }}>
             <div style={{ fontSize: '32px', opacity: 0.4 }}>✦</div>
-            <p className="text-base">Select a session or start a new chat</p>
+            <p className="text-base">Start typing to begin</p>
           </div>
         )}
 
@@ -80,8 +135,7 @@ export default function ChatWindow({ messages, loadingHistory, streaming, onSend
             value={input}
             onChange={e => setInput(e.target.value)}
             onKeyDown={handleKeyDown}
-            disabled={!activeSession}
-            placeholder={activeSession ? 'Message NexusAI...' : 'Select a session to start chatting'}
+            placeholder="Message NexusAI..."
             rows={1}
             style={{
               flex: 1,
@@ -115,7 +169,7 @@ export default function ChatWindow({ messages, loadingHistory, streaming, onSend
           ) : (
             <button
               onClick={handleSend}
-              disabled={!activeSession || !input.trim()}
+              disabled={!input.trim()}
               className="btn-primary"
               style={{
                 width: '32px',