feat(prompts): inject palace wake-up context into Smart Actions

Enrich the system prompt with L0/L1/L2 workspace context from the
palace when running Smart Actions. Best-effort — failures never block
prompt execution. Gives LLM access to decisions, preferences, and
semantically relevant memories from the workspace.

backend/src/modules/note-prompts/routes.ts

@@ -105,7 +105,7 @@ export async function notePromptRoutes(app: FastifyInstance): Promise<void> {
 
     const noteBody = note.body?.replace(/<[^>]*>/g, ' ').replace(/\s+/g, ' ').trim() ?? '';
 
-    const result = await executePrompt(template, input, noteBody);
+    const result = await executePrompt(template, input, noteBody, userId);
     return result;
   });
 
@@ -148,7 +148,7 @@ export async function notePromptRoutes(app: FastifyInstance): Promise<void> {
     void reply.hijack();
 
     try {
-      const result = await executePrompt(template, input, noteBody);
+      const result = await executePrompt(template, input, noteBody, userId);
       // Stream the result as a series of SSE events: tokens then done
       const chunks = result.content.match(/.{1,80}/g) ?? [result.content];
       for (const chunk of chunks) {

backend/src/modules/note-prompts/runner.ts

@@ -5,6 +5,8 @@
 import { llm } from '../../lib/llm.js';
 import { config } from '../../lib/config.js';
 import { trackEvent } from '../../lib/telemetry.js';
+import { buildNoteLettWakeUp } from '../palace/wakeup.js';
+import { PRODUCT_ID } from '../../lib/product-config.js';
 import {
   buildVisionMessage,
   hasVisionContent,
@@ -34,6 +36,7 @@ export async function executePrompt(
   template: PromptTemplateDoc,
   input: RunPromptInput,
   noteBody: string,
+  userId?: string,
 ): Promise<RunPromptOutput> {
   const provider = llm();
 
@@ -52,9 +55,20 @@ export async function executePrompt(
 
   const userPrompt = interpolate(template.userPromptTemplate, vars);
 
+  // Enrich system prompt with palace wake-up context (best-effort)
+  let systemPrompt = template.systemPrompt;
+  if (config.PALACE_ENABLED && input.workspaceId) {
+    try {
+      const wakeUp = await buildNoteLettWakeUp(userId ?? '', PRODUCT_ID, input.workspaceId);
+      if (wakeUp.text) {
+        systemPrompt += `\n\n## Workspace Context\n${wakeUp.text}`;
+      }
+    } catch { /* best-effort — don't block prompt execution */ }
+  }
+
   // Build messages
   const messages: ChatMessage[] = [
-    { role: 'system', content: template.systemPrompt },
+    { role: 'system', content: systemPrompt },
   ];
 
   if (input.imageUrl && (template.inputType === 'image' || template.inputType === 'text+image')) {