Two profiles on one host default to the same bridge_port (3000) but have
profile-scoped session paths. _reuse_running_bridge adopted any connected
bridge whose scriptHash and read-receipt config matched, so profile B
adopted profile A's bridge and served A's session; on any mismatch,
connect() fell through to the pidfile/port kill path and killed A's
running bridge.
Contract, keyed on a new /health `session` field (normalized absolute
session dir via bridge_helpers.js sessionIdentity):
1. session present and EQUAL to the adapter's own normalized session
path -> today's logic unchanged (adopt on hash + read-receipt match,
else stale/restart).
2. session present and DIFFERENT -> FOREIGN bridge: not adopted, not
killed. connect() sets a fatal error naming the port, the foreign
session path, and the fix (platforms.whatsapp.extra.bridge_port, one
distinct port per profile).
3. session ABSENT (bridge predates the handshake) -> treated as stale
and restarted, exactly like an absent scriptHash today.
Normalization uses Node path.resolve / Python os.path.abspath - absolute
and `..`-normalized WITHOUT symlink resolution. fs.realpathSync /
Path.resolve() would resolve symlinks asymmetrically (macOS
/tmp -> /private/tmp) and produce false foreign verdicts.
(cherry picked from commit 7e8418678e91fa4bc69d4b4fa6faedd66f2a80e5)
ff32607c6f