Allow `corepack use` with default package manager when network disabled `COREPACK_ENABLE_NETWORK=0`

What would you like?

corepack use should default to the package manager version stored in lastKnownGood.json when network connections are disabled with COREPACK_ENABLE_NETWORK=0.

For example

corepack use yarn

should work if previously Yarn was globally installed:

corepack install -g yarn@<specific-version>

Why is this needed?

Version-independent workflows including for example corepack use yarn should still work with no network available.

Steps to reproduce

Ubuntu 22.04.2 LTS, Node.js 22.14.0 LTS, Corepack 0.32.0

rm -rf ~/.cache/node/corepack
corepack install -g yarn@4.8.0

export COREPACK_ENABLE_NETWORK=0
cd $(mktemp -d)
corepack use yarn # fails
corepack use yarn@4.8.0 # succeeds

Logs

Failure

$ corepack use yarn # fails
Usage Error: Network access disabled by the environment; can't reach npm repository https://registry.npmjs.org

$ corepack use <pattern>

Success

$ corepack use yarn@4.8.0 # succeeds
Installing yarn@4.8.0 in the project...

➤ YN0000: · Yarn 4.8.0
➤ YN0000: ┌ Resolution step
➤ YN0000: └ Completed
➤ YN0000: ┌ Fetch step
➤ YN0000: └ Completed
➤ YN0000: ┌ Link step
➤ YN0000: └ Completed
➤ YN0000: · Done in 0s 78ms

Start at the corepack use command entry point and trace how a package manager version is resolved when COREPACK_ENABLE_NETWORK=0. Reproduce the failure using the commands and environment in the issue, then verify that corepack use yarn selects the globally installed version from lastKnownGood.json without network access.