Progress indication for long operations

A CLI that sits silent for ten seconds during a deploy looks frozen. Users hit Ctrl+C, corrupt state, and open a support ticket. Progress indicators on stderr — spinners, counters, bars — tell the user the tool is alive without polluting stdout for scripts. Writing spinners to stdout is the opposite failure: mytool deploy | tee log captures terminal control sequences into the log file, and every subsequent cat log flickers the terminal.

Wrap operations over two seconds (network calls, installs, file scans) with a spinner or progress bar routed to stderr, and suppress when !process.stderr.isTTY. In src/cli/commands/deploy.ts:

import ora from 'ora'
const spinner = ora({ text: 'Deploying...', stream: process.stderr }).start()
try { await deploy(); spinner.succeed('Deployed') }
catch (e) { spinner.fail('Failed'); throw e }