Adds an exact-key tier (ALLOWED_ENV_KEYS) beside ALLOWED_ENV_PREFIXES in
schemas.ts, admitting CLAUDE_CONFIG_DIR so a case can run on a separate
Claude subscription (client-billed accounts). Exact match only: other
CLAUDE_* keys and near-misses like CLAUDE_CONFIG_DIR_EXTRA stay rejected,
blocked keys stay blocked. The key also survives getEnvOverridesForPersist()
(a path, not a secret; dropping it would silently switch a rebuilt session
back to the default account after a reboot).
Docs cover the transcript caveat: a relocated config dir writes transcripts
outside ~/.claude/projects, so response viewer / subagent windows /
ultracode / Read My Mind go blind for that session unless projects is
symlinked back into the shared tree.
Design and spec contributed by @jordan8037310 in #255. Closes#255.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
