v0.5.6

What's Changed

• Add minLamport for proper GC of deactivated clients by @JOOHOJANG in #1060
• Optimize document detachment in Cluster Server by @raararaara in #1055
• Upate garbage collection algorithm design by @JOOHOJANG in #1061
• Fix version vector cleanup during client deactivation by @raararaara in #1068
• Convert presence change from string to binary by @chacha912 in #1069
• Add migration script to detach documents from deactivated clients by @raararaara in #1062
• Correct ReverseLowerBound behavior in MemDB by setting unique index by @chacha912 in #1074
• Update presence_change migration for JSON to Protobuf conversion by @chacha912 in #1075

Full Changelog: v0.5.5...v0.5.6