add Telegram alerts: qualified setups, S/R proximity, score drops, daily digest

Closes the action loop — instead of polling the dashboard, the platform pushes
actionable signals to Telegram. New hourly 'alerts' job dispatches four
toggleable triggers, deduped via a new alert_log table (cooldown-based for
qualified/S-R/digest, watermark-based for score deterioration). Admin → Settings
gains a Telegram panel (write-only bot token, chat ID, per-trigger toggles, Send
Test). Credentials follow DB > env precedence (TELEGRAM_BOT_TOKEN / _CHAT_ID).

Backend: alert_service + AlertLog model + migration 005, scheduler job, admin
endpoints/schema. Frontend: AlertSettings panel, hooks, api, types.

Deploy: run alembic upgrade (new alert_log table).

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

frontend/src/api/admin.ts

@@ -2,6 +2,8 @@ import apiClient from './client';
 import type {
   ActivationConfig,
   AdminUser,
+  AlertConfig,
+  AlertTestResult,
   PipelineReadiness,
   RecommendationConfig,
   SentimentProviderConfig,
@@ -105,6 +107,32 @@ export function testSentimentSettings(ticker: string) {
     .then((r) => r.data);
 }
 
+export function getAlertSettings() {
+  return apiClient
+    .get<AlertConfig>('admin/settings/alerts')
+    .then((r) => r.data);
+}
+
+export function updateAlertSettings(payload: {
+  enabled?: boolean;
+  bot_token?: string;
+  telegram_chat_id?: string;
+  qualified_enabled?: boolean;
+  sr_proximity_enabled?: boolean;
+  score_drop_enabled?: boolean;
+  digest_enabled?: boolean;
+}) {
+  return apiClient
+    .put<AlertConfig>('admin/settings/alerts', payload)
+    .then((r) => r.data);
+}
+
+export function testAlertSettings() {
+  return apiClient
+    .post<AlertTestResult>('admin/settings/alerts/test')
+    .then((r) => r.data);
+}
+
 export function getTickerUniverseSetting() {
   return apiClient
     .get<TickerUniverseSetting>('admin/settings/ticker-universe')