Migrate to TypeScript (#1)

* rf: js -> ts

* [m] docs: add badges, lint

spamwatch.js

@@ -1,28 +0,0 @@
-const fs = require('fs');
-const path = require('path');
-
-const blocklistPath = path.join(__dirname, 'sw_blocklist.txt');
-
-let blocklist = [];
-
-const readBlocklist = () => {
-  try {
-    const data = fs.readFileSync(blocklistPath, 'utf8');
-    blocklist = data.split('\n').map(id => id.trim()).filter(id => id !== '');
-  } catch (error) {
-    if (error.code === 'ENOENT') {
-      console.log('WARN: SpamWatch blocklist file not found. Creating a new, blank one.\nUse your own SpamWatch API key and our generator to push the blocklist to the file.');
-      fs.writeFileSync(blocklistPath, '');
-    } else {
-      console.error('WARN: Error reading SpamWatch blocklist:', error);
-    }
-  }
-};
-
-const isOnSpamWatch = (userId) => {
-  return blocklist.includes(String(userId));
-};
-
-readBlocklist();
-
-module.exports = { isOnSpamWatch };