feat(updater): add feed-config to map channel setting to feed URL

src/main/updater/feed-config.js

@@ -0,0 +1,31 @@
+const REPO = 'amitwh/markdown-converter';
+
+const FEEDS = {
+  github: {
+    base: `https://github.com/${REPO}/releases/download`,
+  },
+  concreteinfo: {
+    base: 'https://updates.concreteinfo.co.in/v5',
+  },
+};
+
+function platformSuffix(platform) {
+  if (platform === 'darwin' || platform === 'mac') return 'mac';
+  if (platform === 'win32' || platform === 'windows') return 'windows';
+  return 'linux';
+}
+
+function feedForChannel(channel, version, platform) {
+  const suffix = platformSuffix(platform);
+  const f = FEEDS[channel] || FEEDS.github;
+  if (channel === 'github') {
+    return `${f.base}/v${version}/latest-${suffix}.yml`;
+  }
+  return `${f.base}/latest-${suffix}.yml`;
+}
+
+function resolveFeedUrl(channel, version, platform) {
+  return feedForChannel(channel, version, platform);
+}
+
+module.exports = { resolveFeedUrl, FEEDS };