Reference creatortrack worktree dev turbopack symlink

Two gotchas when standing up a CreatorTrack parallel-dev slot via forge_creatortrack_agent_bootstrap.sh <branch> <port>:

  1. next dev now defaults to Turbopack, which panics on the worktree's node_modules symlink. The bootstrap symlinks node_modules -> /home/justinwieb/forge-suite/node_modules (main's). Turbopack aborts with Symlink [project]/node_modules is invalid, it points out of the filesystem root and the server never binds. Fix: launch with the webpack builder instead: ./node_modules/.bin/next dev --webpack -p <port>. (--webpack is a valid next dev flag alongside --turbopack.) This only affects how the dev server is launched, not committed code.

  2. A slash in the branch name breaks the bootstrap's dev-server log redirect. For feat/foo, the script writes to /tmp/ct-agent-feat/foo.log but only mkdirs /tmp/ct-agent, so the redirect fails and the auto-started server dies. Fix: mkdir -p /tmp/ct-agent-<firstsegment> then launch manually.

  3. Detach cleanly. pkill -f 'next dev...' from the agent shell can also kill the just-launched nohup child (exit 144). Use setsid bash -c '... > log 2>&1' < /dev/null & disown so the server fully detaches from the agent shell.

Distinct from [[reference_turbopack_root_widening_bug]] (that was turbopack.root widening to crawl all worktrees; this is the cross-root symlink rejection).