fix(install): seed pnpm workspace members and catalog deps (#35376)
Seeding a deno.lock from a sibling pnpm-lock.yaml only read the root
importer, so dependencies declared by workspace members were dropped and
specifiers using pnpm's catalog: protocol were skipped entirely. A
monorepo therefore seeded an incomplete lock, and a lock whose deps all
used catalog: seeded an empty one while still printing "Seeded deno.lock
from ...", which was misleading.
This iterates every importer when translating, mapping the root to the
top-level workspace.packageJson section and each non-root importer to
workspace.members.<path>. catalog: and catalog:<name> specifiers are
resolved to their real version requirement via the lockfile's top-level
catalogs: block (bare catalog: uses the default catalog). The "Seeded"
message is now only emitted when the translation actually produced
content, so a lockfile with only file:/link: deps no longer claims to
have seeded anything.
Follows up on #35346.