v0.0.1

Added

• RocksDB-backed world storage: leveldb::DB::Open is hooked (LL_AUTO_STATIC_HOOK on the 23-byte
  prologue, _sig) and MC receives an McRocksDb that implements the real leveldb::DB vtable, backed
  by RocksDB (rocksdb v11.1.2, no compression, 4 MB write buffer, 4 KB blocks, 80 MB LRU block cache,
  bloom filter 10).
• One-time migration of an existing LevelDB world into a sibling rocksdb directory, batched in 4096-key
  WriteBatches, flushed and WAL-synced; the LevelDB db directory is left untouched. Failed migrations
  abort non-destructively and report IOError.
• config.json (enabled, migrateExisting) loaded through ll::config.
• Vendored origin/main sources of Mojang's LevelDB fork (src/leveldb, src/db, src/util) so the
  interception boundary uses the real leveldb:: classes instead of a mirrored ABI.

Fixed

• McRocksDb::Get now accepts a null value, which MC uses as an existence probe (Mojang's LevelDB only
  copies the payload when a string is given: MemTable::Get, Version::Get). RocksDB always copies, so
  the value is read into a PinnableSlice and dropped. Previously this aborted the server at world load.