…ache

If the library pack containing the AST query does not have
a lock file, it is likely to be in the package cache, not
a checkout of the CodeQL repo.
In this case, use `codeql pack resolve-dependencies`
to create a temporary lock file, and `codeql pack install`
to install the dependencies of this library pack.

This allows the CLI to resolve the library path and
dependencies for the AST query before running it.

Clear the CLI server's pack cache before installing packs,
to avoid race conditions where the new lock file is not
detected during query running.

Adjust some helper methods.

Shared by the AST viewer, jump to def, and find references
contextual queries.

This allows contextual queries to have their dependencies
resolved and be run whether the library pack is in the
workspace or in the package cache.