Workspace UI overhaul: rail note panel, split task detail, project goal header

- WorkspaceNoteEditor: replace toggling list/editor views with always-visible
  left rail (155px) showing note list alongside editor pane; persist last-open
  note per project in localStorage (workspace_note_{projectId})
- WorkspaceTaskPanel: add priority dot + due date on task rows; replace full
  overlay detail with bottom-split (44% list / 56% detail); close button
  replaces back nav; active row highlighted; fade transition
- WorkspaceView: show project goal in header instead of 'Workspace'; non-equal
  panel widths (0.8fr / 1.1fr / 1.1fr); empty chat quick-action chips (Project
  status / New note / Add tasks); prefill() helper

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/src/views/WorkspaceView.vue

@@ -22,6 +22,7 @@ const projectId = computed(() => Number(route.params.projectId));
 interface Project {
   id: number;
   title: string;
+  goal?: string;
 }
 
 const project = ref<Project | null>(null);
@@ -56,12 +57,11 @@ function _loadPanelState(pid: number) {
 const panelOpen = ref({ tasks: true, chat: true, notes: true });
 
 const gridColumns = computed(() => {
-  const cols = [
-    panelOpen.value.tasks ? "1fr" : "0px",
-    panelOpen.value.chat ? "1fr" : "0px",
-    panelOpen.value.notes ? "1fr" : "0px",
-  ];
-  return cols.join(" ");
+  return [
+    panelOpen.value.tasks ? "minmax(0, 0.8fr)" : "0px",
+    panelOpen.value.chat  ? "minmax(0, 1.1fr)" : "0px",
+    panelOpen.value.notes ? "minmax(0, 1.1fr)" : "0px",
+  ].join(" ");
 });
 
 // SSE watcher
@@ -124,6 +124,11 @@ function togglePanel(panel: keyof typeof panelOpen.value) {
   localStorage.setItem(_panelKey(projectId.value), JSON.stringify(panelOpen.value));
 }
 
+function prefill(text: string) {
+  messageInput.value = text;
+  nextTick(() => inputEl.value?.focus());
+}
+
 async function sendMessage() {
   const content = messageInput.value.trim();
   if (!content) return;
@@ -230,7 +235,7 @@ onUnmounted(async () => {
       <router-link :to="project ? `/projects/${project.id}` : '/projects'" class="ws-back">
         ← {{ project?.title ?? "Project" }}
       </router-link>
-      <span class="ws-title">Workspace</span>
+      <span class="ws-title">{{ project?.goal ?? '' }}</span>
       <div class="ws-panel-toggles">
         <button
           :class="['panel-toggle', { active: panelOpen.tasks }]"
@@ -341,12 +346,17 @@ onUnmounted(async () => {
             </div>
           </template>
 
-          <p
+          <div
             v-if="chatStore.currentConversation && !chatStore.currentConversation.messages.length && !chatStore.streaming"
-            class="empty-chat-msg"
+            class="empty-chat-prompt"
           >
-            Ask the agent to create notes or tasks for this project.
-          </p>
+            <p class="empty-hint">What would you like to work on?</p>
+            <div class="quick-chips">
+              <button class="quick-chip" @click="prefill('Summarize the current status of this project')">📊 Project status</button>
+              <button class="quick-chip" @click="prefill('Create a note about ')">📝 New note</button>
+              <button class="quick-chip" @click="prefill('Add tasks for ')">✓ Add tasks</button>
+            </div>
+          </div>
         </div>
 
         <div class="chat-input-area">
@@ -428,10 +438,13 @@ onUnmounted(async () => {
 }
 
 .ws-title {
-  font-weight: 600;
-  font-size: 0.9rem;
+  font-size: 0.78rem;
   color: var(--color-text-muted);
   flex: 1;
+  overflow: hidden;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+  font-style: italic;
 }
 
 .ws-panel-toggles {
@@ -501,12 +514,37 @@ onUnmounted(async () => {
   gap: 0.75rem;
 }
 
-.empty-chat-msg {
-  color: var(--color-text-muted);
-  font-size: 0.875rem;
+.empty-chat-prompt {
   text-align: center;
   padding: 2rem 1rem;
 }
+.empty-hint {
+  margin: 0 0 1rem;
+  color: var(--color-text-secondary);
+  font-size: 0.9rem;
+}
+.quick-chips {
+  display: flex;
+  flex-wrap: wrap;
+  gap: 0.5rem;
+  justify-content: center;
+}
+.quick-chip {
+  background: var(--color-surface);
+  border: 1px solid var(--color-border);
+  border-radius: 20px;
+  padding: 0.4rem 0.85rem;
+  font-size: 0.82rem;
+  color: var(--color-text-secondary);
+  cursor: pointer;
+  transition: border-color 0.15s, color 0.15s, background 0.15s;
+  font-family: inherit;
+}
+.quick-chip:hover {
+  border-color: var(--color-primary);
+  color: var(--color-primary);
+  background: color-mix(in srgb, var(--color-primary) 5%, var(--color-surface));
+}
 
 .chat-input-area {
   display: flex;