sync-tsdown-cli

name	sync-tsdown-cli
description	Sync tsdown runtime CLI options with vp pack after a tsdown upgrade. Use for option forwarding changes; use sync-upstream-cli-help for static help wording.
allowed-tools	Read, Grep, Glob, Edit, Bash

Sync tsdown CLI

Runtime options live in packages/cli/src/pack-bin.ts; static help lives in packages/cli/src/help.ts.

1. Run npx tsdown --help from packages/cli/ and compare it with pack-bin.ts.
2. Add new forwarded options using the existing cac .option() pattern. For removed options, add // NOTE: removed from tsdown CLI in vX.Y.Z for reviewer follow-up.
3. Preserve runtime differences: -c, --config stays disabled because Vite+ uses vite.config.ts, and --env-prefix keeps the ['VITE_PACK_', 'TSDOWN_'] default.
4. For static labels and descriptions, follow sync-upstream-cli-help; do not adapt upstream wording to explain runtime differences.
5. Run pnpm --filter vite-plus build-ts and vp pack -h. Add a focused PTY snapshot case under crates/vp_cli_snapshots/tests/cli_snapshots/fixtures/ when a new runtime option is exposed.