feat(ui): chip projet dans le composer + aperçu réductible

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

frontend/src/panels/ChatPanel.tsx

@@ -3,6 +3,7 @@ import { useStore } from "../store/useStore";
 import { ChevronDown, LokiMark, SendIcon } from "../components/Icon";
 import { ToolCard } from "../components/ToolCard";
 import { MessageContent } from "../components/MessageContent";
+import { ProjectChip } from "../components/ProjectChip";
 import type { Message, ToolCall } from "../api/client";
 
 /** Panneau central : barre de contexte, fil de conversation, composer. */
@@ -136,6 +137,7 @@ export function ChatPanel() {
             />
             <div className="mt-1.5 flex items-center gap-2">
               <ModeSelector />
+              <ProjectChip />
               <div
                 className="flex h-8 min-w-0 max-w-[180px] items-center gap-1.5 border-2 border-line px-2.5 text-[13px] text-ink-2"
                 title={selectedModel || undefined}