Making RedisParser::Buffer const, some minor changes in dragonfly_connection code.
No functionality is changed.
Signed-off-by: Roman Gershman <roman@dragonflydb.io>
* fix: ZINTERSTORE bug
When a shard only contains the dest key, it returned an empty map which causes the resulting intersection to be empty
* chore(vscode): Add gdb launch setting
* feat: Implement ZINTERCARD
Initial implementation without LIMIT
* feat: Implement limit for ZINTERCARD
* feat: Handle sets in ZINTER* commands
1. Make EngineShardSet to be a process singleton instead of a variable passed everywhere.
2. Implement a heuristic of updating free memory per shard.
3. Make sure that SET command returns OOM when a database reaches its limits.
