v4.20.4

## What's Changed

### Bug Fixes
* fix(effects): stop replica SIGSEGV on UPDATE_EDGE/UPDATE_NODE divergence - replicas no longer crash when an effect references a node or edge that no longer exists locally; the mismatch is now detected and triggers a full resync instead (#2581)

### Performance
* remove full sync from decoder - transpose matrices are rebuilt incrementally as delta-matrix components are set during RDB decoding instead of forcing a full sync at the end, speeding up loading of persisted graphs (#2584)

### Improvements
* serializers: export Graph_EncodingVersion and Graph_GetDecoder - new public APIs let external modules (e.g. graph-offloading) stamp dumps with their encoding version and select the matching decoder on load (#2552)

**Full Changelog**: https://github.com/FalkorDB/FalkorDB/compare/v4.20.3...v4.20.4