feat: add metrics tracking and remove unsupported HMAC verification

- Add metrics.js tracking webhooks, messages, cron, commands
- Add GET /metrics/:secret endpoint (text + JSON format)
- Remove HMAC verification (Statuspage doesn't support it)
- Extract validateSecret helper in index.js
- Integrate trackMetrics across webhook, queue, cron, bot handlers

src/bot-commands.js

@@ -8,6 +8,7 @@ import {
 } from "./kv-store.js";
 import { fetchComponentByName, escapeHtml } from "./status-fetcher.js";
 import { registerInfoCommands } from "./bot-info-commands.js";
+import { trackMetrics } from "./metrics.js";
 
 /**
  * Extract chatId and threadId from grammY context
@@ -26,6 +27,12 @@ export async function handleTelegramWebhook(c) {
   const bot = new Bot(c.env.BOT_TOKEN);
   const kv = c.env.claude_status;
 
+  // Track command usage
+  bot.use(async (ctx, next) => {
+    await trackMetrics(kv, { commandsProcessed: 1 });
+    await next();
+  });
+
   bot.command("start", async (ctx) => {
     const { chatId, threadId } = getChatTarget(ctx);
     await addSubscriber(kv, chatId, threadId);