feat: a new chat is named by the model in two or three words, asked aside; the machine's name gets its room in the chat's header

internal/server/web/static/app.css

@@ -852,7 +852,10 @@ body.touch.term-active .ai-fab { bottom:104px; }
 .ai-fab:hover { transform:scale(1.06); box-shadow:0 10px 28px rgba(91,140,255,.45); }
 .ai-head { display:flex; align-items:center; gap:8px; padding:10px 12px; border-bottom:1px solid var(--border); }
 /* The machine the chat sees: its name on one line, cut with … */
-.ai-head .ai-where { flex:0 1 auto; min-width:0; max-width:30%; font-size:12px; white-space:nowrap; overflow:hidden; text-overflow:ellipsis; }
+/* The machine's name: room for 7-8 letters at least, the chat's name gives way. */
+.ai-head .ai-where { flex:0 0 auto; min-width:0; max-width:40%; font-size:12px; white-space:nowrap; overflow:hidden; text-overflow:ellipsis; }
+.ai-head .ai-chatsel { min-width:0; }
+.ai-head .ai-chatname { min-width:3ch; }
 .ai-head .ai-chatsel { flex:0 1 auto; }
 .ai-list { flex:1; overflow:auto; padding:12px; display:flex; flex-direction:column; gap:10px; }
 .ai-msg { max-width:92%; padding:8px 11px; border-radius:10px; font-size:14px; line-height:1.45; overflow-wrap:anywhere; }