convSessions held the DingTalk-conversation to agent-session map purely
in memory, so a connector restart dropped every chat's multi-turn
context - the core weakness of an always-on digital employee.
Persist the map to ~/.dws/connect/<clientId>/sessions.json (scoped per
clientId so multiple bots on one machine stay isolated), reusing the
existing config dir, 0600 FilePerm and lock-id sanitizer conventions:
- newConvSessions restores the map on startup; a missing or corrupt
file degrades to an empty map with a warning, never a panic or a
blocked connection.
- args/reset persist after every mutation, under the existing mutex so
the snapshot is race-free, via a temp-file + rename atomic write.
- saves are best-effort: a write failure only logs a warning and never
blocks message handling.
- an empty path (clientId missing or --agent-memory off) keeps the map
in memory only, preserving the original behaviour exactly.
forwarderForChannel now takes clientId to derive the per-bot store path.
Adds unit tests for reload, corrupt-file degradation, in-memory mode and
concurrent access (race-clean).
修雨
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