Add RAG semantic search and proactive event notifications

Implement hybrid knowledge search using Cloudflare Vectorize + Workers AI
embeddings (bge-base-en-v1.5, 768d) merged with existing D1 LIKE queries,
with graceful degradation when Vectorize is unavailable. Add admin API
endpoints for batch/single article indexing.

Add 4 proactive notification cron jobs: server status changes, deposit
confirmation/rejection alerts, pending payment reminders (1h+), and bank
deposit matching notifications — all with DB-column-based deduplication.

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

src/routes/api.ts

@@ -2,6 +2,7 @@ import { Hono } from 'hono';
 import type { Env, User, Transaction } from '../types';
 import { timingSafeEqual } from '../security';
 import { getPendingActions } from '../services/pending-actions';
+import { indexArticle, batchIndexArticles } from '../services/embedding';
 import { sendMessage } from '../telegram';
 import { createLogger } from '../utils/logger';
 
@@ -171,4 +172,67 @@ api.post('/broadcast', async (c) => {
   }
 });
 
+// POST /api/knowledge/index - Batch index all knowledge articles
+api.post('/knowledge/index', async (c) => {
+  try {
+    if (!c.env.VECTORIZE) {
+      return c.json({ error: 'VECTORIZE binding not configured' }, 400);
+    }
+
+    const body = await c.req.json<{ force_reindex?: boolean }>().catch(() => ({ force_reindex: false }));
+    const result = await batchIndexArticles(c.env, {
+      forceReindex: body.force_reindex ?? false,
+    });
+
+    logger.info('Knowledge batch indexing completed', {
+      indexed: result.indexed,
+      failed: result.failed,
+    });
+    return c.json(result);
+  } catch (error) {
+    logger.error('Knowledge batch indexing failed', error as Error);
+    return c.json({ error: 'Internal error' }, 500);
+  }
+});
+
+// POST /api/knowledge/:id/index - Index a single knowledge article
+api.post('/knowledge/:id/index', async (c) => {
+  try {
+    if (!c.env.VECTORIZE) {
+      return c.json({ error: 'VECTORIZE binding not configured' }, 400);
+    }
+
+    const articleId = parseInt(c.req.param('id'));
+    if (isNaN(articleId)) {
+      return c.json({ error: 'Invalid article ID' }, 400);
+    }
+
+    const article = await c.env.DB
+      .prepare(
+        `SELECT id, category, title, content, tags
+         FROM knowledge_articles WHERE id = ? AND is_active = 1`
+      )
+      .bind(articleId)
+      .first<{ id: number; category: string; title: string; content: string; tags: string | null }>();
+
+    if (!article) {
+      return c.json({ error: 'Article not found' }, 404);
+    }
+
+    await indexArticle(
+      c.env,
+      article.id,
+      article.title,
+      article.content,
+      article.category,
+      article.tags ?? undefined
+    );
+
+    return c.json({ success: true, articleId: article.id });
+  } catch (error) {
+    logger.error('Knowledge article indexing failed', error as Error);
+    return c.json({ error: 'Internal error' }, 500);
+  }
+});
+
 export { api as apiRouter };