v0.5.1

allow xcrun cache writes in seatbelt profile so git works on macOS (#26)

Every git call inside the macOS sandbox printed "confstr() failed with
code 5: couldn't get path of DARWIN_USER_TEMP_DIR" followed by "couldn't
create cache file '/tmp/xcrun_db-*' (Operation not permitted)" because
the base seatbelt profile denied (a) the mach-lookup of dirhelper that
confstr uses to resolve $TMPDIR and (b) writes to both /private/tmp and
/private/var/folders/<uid>/T/ where xcrun caches its sqlite db. The
sandbox was effectively unusable for any Developer Tools workflow.

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>