feat: add validium support external node (Moved)

[toni-calvin]

Closes #167

Summary

1. This pull request addresses the need to dynamically set the L1CommitGeneratorMode of the external node based on the configuration value l1_batch_commit_data_generator_mode in the etc/env/ext-node.toml file. If the configuration value is set, the external node will be configured for Validium; otherwise, the default mode will be Rollup.

Changes Made

1. Added logic to check for the presence of l1_batch_commit_data_generator_mode in etc/env/ext-node.toml.
2. If the value is set, the L1CommitGeneratorMode of the external node is set to "validium."
3. If the value is not set, the default mode "rollup" is used.
4. Users can manually update the configuration by adding l1_batch_commit_data_generator_mode="Validium" to the ext-node.toml file.