fix(shadow): scan only the dlx package with IPC token

[Martin Torp (mtorp)]

What

The pnpm and yarn shadow bins now honor the IPC overrides that internal callers pass, and dlx only scans the package being launched.

Why

When socket scan create --reach runs in a pnpm or yarn project, the CLI launches Coana with pnpm dlx or yarn dlx through the shadow bin. Before running, the shadow bin checks the package with POST /v0/purl. Two things went wrong there.

1. Wrong token. spawnCoanaDlx (and runCdxgen) pass SOCKET_CLI_SHADOW_API_TOKEN: SOCKET_PUBLIC_API_TOKEN and SOCKET_CLI_SHADOW_ACCEPT_RISKS: true over IPC. The npm/npx path forwards these to the injected arborist. The pnpm and yarn bins ignored them and called the purl endpoint with the user's own token. The purl endpoint rejects repository-scoped tokens, so every reachability run with one printed Received a 403 response from Socket API which we consider a permanent failure: ... This endpoint does not support repository-scoped tokens. The run kept going, but it reads as an auth failure in CI logs.
2. Wrong packages. The dlx scan treated every positional argument as a package. For Coana that meant run, the analysis timeout, the memory limit and the manifests tar hash were all looked up as npm packages, e.g. pkg:npm/run. Because accept-risks was also ignored, an alert on any of those names would have made the shadow bin exit 1 and kill the scan.

How

• scanPackagesAndLogAlerts takes an optional apiToken and passes it to getAlertsMapFromPurls. When it's unset, the token falls back to the default, same as before.
• shadowPnpmBin and shadowYarnBin read the API token and accept-risks from ipc, the same way the npm arborist does. Calls without IPC overrides, like a user running socket pnpm dlx foo, behave as before.
• dlx scans the package option values, or the first positional if there are none. Later positionals belong to the launched binary. Each shadow bin passes a DlxFlags list naming its package options and the other options that take a value, so values like --allow-build esbuild are skipped before the package is chosen. pnpm uses --package (its -p is --parseable). yarn uses --package and -p.

Testing

• New unit tests in src/shadow/pnpm/bin.test.mts and src/shadow/yarn/bin.test.mts cover dlx with tool arguments, dlx with --package, option values before the package, repeated --package split by another option, pnpm -p as a boolean, and IPC token plus accept-risks. They fail without the fix and pass with it.
• pnpm run check:tsc and pnpm run lint pass.

Workaround for affected users until this ships: SOCKET_CLI_COANA_LAUNCHER=npm-install skips dlx and the shadow scan.

Expected reviewer effort: Full code review

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Note

Medium Risk
Changes API token selection and which packages block dlx in the shadow security gate used before reachability runs; behavior for direct user dlx without IPC is intended to stay the same.

Overview
Fixes pnpm and yarn shadow-bin preflight scans when internal callers launch tools via dlx (e.g. Coana during socket scan create --reach).

The shadow bins now read SOCKET_CLI_SHADOW_API_TOKEN and SOCKET_CLI_SHADOW_ACCEPT_RISKS from IPC (matching npm/npx) and pass the token into getAlertsMapFromPurls, so the pre-download PURL check no longer hits the API with a repository-scoped user token and spurious 403 errors in CI.

dlx parsing is split from add: only --package / -p values (yarn) or --package plus pnpm value-taking flags are considered packages; otherwise the first positional is scanned and later args (e.g. run, timeouts) are ignored. Lockfile scans on pnpm also forward the IPC token.

Unit tests cover Coana-style dlx invocations, --package handling, and IPC overrides.

^{Reviewed by Cursor Bugbot for commit 77c1c66. Configure here.}