fix(recommender): remove Todoist fallback on orchestrator failure; add snooze exclusion

When fetchOrchestratorTip returned null (LiteLLM timeout, bad JSON, etc.)
the recommender silently fell back to randomPolicy, serving a raw Todoist
task with no rationale — explaining both reported symptoms.

- Remove randomPolicy/signalToCandidate; return 204 when orchestrator fails
  so the UI shows "All clear" instead of a confusing Todoist task
- Pass recent_tip through the stack (frontend → POST /recommend →
  fetchOrchestratorTip → ml/serving RecommendRequest → build_orchestrator_messages)
  so after snooze the LLM is instructed not to repeat the snoozed content

Fixes #122

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

services/api/src/routes/recommender.ts

@@ -7,7 +7,7 @@ import { eq, and, desc } from 'drizzle-orm';
 import { requireAuth, AuthenticatedRequest } from '../middleware/session.js';
 import { config } from '../config.js';
 import { bus } from '../events/bus.js';
-import type { TipCandidate, Signal } from '@oo/shared-types';
+import type { Tip, Signal } from '@oo/shared-types';
 import { todoistSource, dueAgeDays } from '../signals/todoist.js';
 export { dueAgeDays };
 import { googleHealthSource } from '../signals/google-health.js';
@@ -26,32 +26,12 @@ export const _clearSignalCacheForTests = () => {
   googleHealthSource.clearCache();
 };
 
-// ---------------------------------------------------------------------------
-// Signal → TipCandidate conversion
-// ---------------------------------------------------------------------------
-function signalToCandidate(signal: Signal): TipCandidate {
-  return {
-    id: signal.id,
-    content: signal.content,
-    source: signal.source as TipCandidate['source'],
-    kind: signal.kind as TipCandidate['kind'],
-    sourceId: (signal.metadata.todoistId as string | undefined) ?? undefined,
-    createdAt: signal.timestamp,
-    features: signal.features,
-  };
-}
-
-function randomPolicy(candidates: TipCandidate[]): TipCandidate | null {
-  if (!candidates.length) return null;
-  return candidates[Math.floor(Math.random() * candidates.length)];
-}
-
 // ---------------------------------------------------------------------------
 // Orchestrator: fetch agent snippets + call ml/serving /recommend
 // ---------------------------------------------------------------------------
 
 interface OrchestratorResult {
-  tip: TipCandidate;
+  tip: Tip;
   model: string | null;
   agentIds: string[];
 }
@@ -72,6 +52,7 @@ async function fetchOrchestratorTip(
   hour: number,
   dayOfWeek: number,
   traceparent?: string,
+  recentTip?: string,
 ): Promise<OrchestratorResult | null> {
   const [allAgentRows, eligibleIds, scienceDestiny] = await Promise.all([
     getActiveAgentOutputs(userId),
@@ -93,7 +74,7 @@ async function fetchOrchestratorTip(
     const res = await fetch(`${config.ML_SERVING_URL}/recommend`, {
       method: 'POST',
       headers: { 'Content-Type': 'application/json', ...(traceparent ? { traceparent } : {}) },
-      body: JSON.stringify({ user_id: userId, agent_outputs: agentOutputs, tasks, hour_of_day: hour, day_of_week: dayOfWeek, science_destiny: scienceDestiny ?? 50 }),
+      body: JSON.stringify({ user_id: userId, agent_outputs: agentOutputs, tasks, hour_of_day: hour, day_of_week: dayOfWeek, science_destiny: scienceDestiny ?? 50, recent_tip: recentTip ?? null }),
       signal: AbortSignal.timeout(15_000),
     });
     if (!res.ok) return null;
@@ -110,7 +91,6 @@ async function fetchOrchestratorTip(
         kind: 'advice' as const,
         rationale: data.tip.rationale,
         createdAt: now,
-        features: { is_overdue: false, task_age_days: 0, priority: 1 },
       },
       model: data.model ?? null,
       agentIds: agentOutputs.map((a) => a.agent_id),
@@ -127,6 +107,7 @@ async function fetchOrchestratorTip(
 router.post('/recommend', requireAuth, async (req: AuthenticatedRequest, res: Response) => {
   const hour = new Date().getHours();
   const dayOfWeek = new Date().getDay();
+  const { recent_tip: recentTip } = req.body as { recent_tip?: string };
 
   const anyToken = await db
     .select({ id: integrationTokens.id })
@@ -142,16 +123,16 @@ router.post('/recommend', requireAuth, async (req: AuthenticatedRequest, res: Re
   const signals = await aggregator.fetchAll(req.userId!);
 
   const t0 = Date.now();
-  const orchestrated = await fetchOrchestratorTip(req.userId!, signals, hour, dayOfWeek, req.traceparent);
+  const orchestrated = await fetchOrchestratorTip(req.userId!, signals, hour, dayOfWeek, req.traceparent, recentTip);
   const latencyMs = Date.now() - t0;
 
-  const tip = orchestrated?.tip ?? randomPolicy(signals.map(signalToCandidate));
-  if (!tip) {
+  if (!orchestrated) {
     res.status(204).end();
     return;
   }
 
-  const policy = orchestrated ? 'orchestrator' : 'random';
+  const tip = orchestrated.tip;
+  const policy = 'orchestrator';
   const servedAt = new Date().toISOString();
 
   await db.insert(tipViews).values({ id: nanoid(), userId: req.userId!, tipId: tip.id, servedAt });
@@ -162,16 +143,12 @@ router.post('/recommend', requireAuth, async (req: AuthenticatedRequest, res: Re
     tipId: tip.id,
     policy,
     mlScore: null,
-    featuresJson: JSON.stringify(
-      orchestrated
-        ? { agent_ids: orchestrated.agentIds, hour_of_day: hour, day_of_week: dayOfWeek }
-        : { ...tip.features, hour_of_day: hour, day_of_week: dayOfWeek },
-    ),
-    candidateCount: orchestrated ? 1 : signals.length,
+    featuresJson: JSON.stringify({ agent_ids: orchestrated.agentIds, hour_of_day: hour, day_of_week: dayOfWeek }),
+    candidateCount: 1,
     latencyMs,
     servedAt,
-    promptVersion: orchestrated ? 'v4-orchestrator' : null,
-    llmModel: orchestrated ? orchestrated.model : null,
+    promptVersion: 'v4-orchestrator',
+    llmModel: orchestrated.model,
     tipKind: tip.kind ?? null,
   });