Project-aware assist, link suggestions, project-scoped RAG, semantic search tool, SSE race fix

- Writing assistant: inject project notes as context (definition-tagged first), wikilink suggestions
- Link suggestions: server-side endpoint finds unlinked term occurrences, NoteEditorView sidebar panel
- Project-scoped RAG: ChatView ProjectSelector filters semantic+keyword search to selected project
- Semantic search tool: LLM search_notes upgraded to hybrid semantic (0.40 threshold) + keyword merge
- SSE race condition fix: drain remaining events after stream loop exits in chat.py and notes.py
- RAG_AUTO_SNIPPET raised 800→4000; sidebar include uses full note body; MAX_BODY_CHARS 8000→24000
- Enter-to-submit on writing assistant instruction textareas (note and task editors)
- DiffView: equal-line collapsing with 3-line context around changes

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

frontend/src/views/ChatView.vue

@@ -9,6 +9,7 @@ import ChatMessage from "@/components/ChatMessage.vue";
 import ToolCallCard from "@/components/ToolCallCard.vue";
 import ToolConfirmCard from "@/components/ToolConfirmCard.vue";
 import type { Note } from "@/types/note";
+import ProjectSelector from "@/components/ProjectSelector.vue";
 
 const route = useRoute();
 const router = useRouter();
@@ -46,6 +47,9 @@ const autoInjectedNotes = ref<{ id: number; title: string; score?: number | null
 // Note IDs excluded from auto-injection on next message
 const excludedNoteIds = ref<number[]>([]);
 
+// Project scope for RAG — when set, semantic & keyword search is restricted to this project
+const ragProjectId = ref<number | null>(null);
+
 let prevConvId: number | null = null;
 
 const convId = computed(() => {
@@ -89,6 +93,8 @@ onMounted(async () => {
     if (store.currentConversation?.id !== convId.value) {
       await store.fetchConversation(convId.value);
     }
+    // Reconnect if the last assistant message is still generating (e.g. after page refresh)
+    store.reconnectIfGenerating(convId.value);
   } else {
     await startNewConversation();
   }
@@ -116,6 +122,8 @@ watch(convId, async (newId) => {
     if (store.currentConversation?.id !== newId && !store.isStreamingConv(newId)) {
       await store.fetchConversation(newId);
     }
+    // Reconnect if a prior stream died while the backend was still generating
+    store.reconnectIfGenerating(newId);
     scrollToBottom();
   } else {
     await startNewConversation();
@@ -220,6 +228,7 @@ async function sendMessage() {
     true, // enable thinking in the full chat view
     undefined,
     excludedNoteIds.value.length ? excludedNoteIds.value : undefined,
+    ragProjectId.value,
   );
   sending.value = false;
 
@@ -404,6 +413,14 @@ onUnmounted(() => {
       <button class="btn-new-conv" @click="newConversation">
         + New Chat
       </button>
+
+      <!-- RAG project scope -->
+      <div class="rag-scope-section">
+        <label class="rag-scope-label">Scope notes to project</label>
+        <ProjectSelector v-model="ragProjectId" />
+        <p v-if="ragProjectId" class="rag-scope-hint">RAG search restricted to this project</p>
+      </div>
+
       <div class="conv-list">
         <div
           v-for="conv in store.conversations"
@@ -713,6 +730,28 @@ onUnmounted(() => {
   opacity: 0.9;
 }
 
+.rag-scope-section {
+  padding: 0.5rem 0.75rem 0.25rem;
+  border-bottom: 1px solid var(--color-border);
+}
+
+.rag-scope-label {
+  display: block;
+  font-size: 0.72rem;
+  font-weight: 600;
+  text-transform: uppercase;
+  letter-spacing: 0.05em;
+  color: var(--color-text-muted);
+  margin-bottom: 0.3rem;
+}
+
+.rag-scope-hint {
+  margin: 0.3rem 0 0;
+  font-size: 0.7rem;
+  color: var(--color-primary);
+  font-style: italic;
+}
+
 .conv-list {
   flex: 1;
   overflow-y: auto;