refactor: replace metrics with console.log, remove HMAC

Statuspage doesn't support HMAC signatures - removed all HMAC code.
Replaced KV-based metrics with simple console.log for CF Workers logs.
Queue consumer logs batch summary (sent/failed/retried/removed).

src/bot-commands.js

@@ -8,8 +8,6 @@ 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
  */
@@ -27,12 +25,6 @@ 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);