The Project row stored a sandboxes string array that duplicated what git
already tracks. The /experimental/worktree GET handler now reads from
`Worktree.list()` (git worktree list --porcelain) instead, the write-side
addSandbox/removeSandbox bookkeeping is gone, and the column is dropped
from the schema with a Drizzle migration. The app maps the live list onto
project.worktrees client-side instead of reading project.sandboxes.
Move the Global module from packages/opencode/src/global to packages/core/src/global
to provide a unified location for managing XDG directories and application paths.
This eliminates duplicate path definitions across packages and ensures consistent
access to data, config, cache, state, log, and bin directories throughout the codebase.
