[DTP-950] Handle initial state sync sequence

[VeskeR]

This PR adds necessary realtime client changes to be able to handle new STATE_SYNC messages by the LiveObjects plugin. The pool initialization itself is implemented in https://github.com/ably/ably-js/pull/1890. I would suggest reviewing this PR commit by commit. Bit flag indexes for new bit flags are based on this: https://github.com/ably/realtime/blob/e3d86b386850b81f09745c3ad3360c976173e0b1/go/realtime/lib/channel/flags.go#L22

Tests for SYNC sequence are added in https://github.com/ably/ably-js/pull/1894.

Resolves DTP-950

Summary by CodeRabbit

Summary by CodeRabbit

• New Features

  • Introduced the LiveObjectsPlugin for enhanced state management and message handling.
  • New types and properties added for improved channel modes and options.
  • Enhanced message decoding capabilities.
  • New classes and methods for managing live object data and synchronization processes.

• Bug Fixes

  • Updated protocol message handling to ensure consistency across various platforms.

• Documentation

  • Updated documentation to reflect new interfaces and methods related to the LiveObjectsPlugin.