feat: add onboarding plugin install flow

src/channels/plugins/catalog.ts

@@ -0,0 +1,43 @@
+import type { ChannelMeta } from "./types.js";
+
+export type ChannelPluginCatalogEntry = {
+  id: string;
+  meta: ChannelMeta;
+  install: {
+    npmSpec: string;
+    localPath?: string;
+  };
+};
+
+const CATALOG: ChannelPluginCatalogEntry[] = [
+  {
+    id: "zalo",
+    meta: {
+      id: "zalo",
+      label: "Zalo",
+      selectionLabel: "Zalo (Bot API)",
+      docsPath: "/channels/zalo",
+      docsLabel: "zalo",
+      blurb: "Vietnam-focused messaging platform with Bot API.",
+      aliases: ["zl"],
+      order: 80,
+      quickstartAllowFrom: true,
+    },
+    install: {
+      npmSpec: "@clawdbot/zalo",
+      localPath: "extensions/zalo",
+    },
+  },
+];
+
+export function listChannelPluginCatalogEntries(): ChannelPluginCatalogEntry[] {
+  return [...CATALOG];
+}
+
+export function getChannelPluginCatalogEntry(
+  id: string,
+): ChannelPluginCatalogEntry | undefined {
+  const trimmed = id.trim();
+  if (!trimmed) return undefined;
+  return CATALOG.find((entry) => entry.id === trimmed);
+}