Introduce Isolated Mode for Sync Handling

[devendran-m]

Retrospective ticket for the pull request - #5021

User Story:
As a node operator, I want an Isolated mode for sync handling so that the node can operate independently of peers in KeepUp mode and query data through the binary port with an existing LMDB database.

Description:
The "Isolated" mode enables a node to bypass peer synchronization when switching to KeepUp mode. This feature is particularly useful for setups with pre-existing LMDB databases, allowing data queries through the binary port without requiring peer interaction.

Acceptance Criteria:

• Node can run in "Isolated" mode without syncing with peers in KeepUp mode.
• Data queries through the binary port function seamlessly with an existing LMDB database.
• Proper documentation and configuration options are provided for enabling Isolated mode.