Slack onboarding: improve token help note with manifest option (openclaw#30846) thanks @yzhong52

Verified:
- pnpm install --frozen-lockfile
- pnpm build
- pnpm check
- pnpm test:macmini

Co-authored-by: yzhong52 <3712071+yzhong52@users.noreply.github.com>
Co-authored-by: Tak Hoffman <781889+Takhoffman@users.noreply.github.com>

src/channels/plugins/onboarding/slack.ts

@@ -99,9 +99,9 @@ async function noteSlackTokenHelp(prompter: WizardPrompter, botName: string): Pr
   const manifest = buildSlackManifest(botName);
   await prompter.note(
     [
-      "1) Slack API → Create App → From scratch",
+      "1) Slack API → Create App → From scratch or From manifest (with the JSON below)",
       "2) Add Socket Mode + enable it to get the app-level token (xapp-...)",
-      "3) OAuth & Permissions → install app to workspace (xoxb- bot token)",
+      "3) Install App to workspace to get the xoxb- bot token",
       "4) Enable Event Subscriptions (socket) for message events",
       "5) App Home → enable the Messages tab for DMs",
       "Tip: set SLACK_BOT_TOKEN + SLACK_APP_TOKEN in your env.",