Implement lazy loading of subcommands for CLI

[ankatiyar]

Description

Based on the discussion in kedro-org/kedro#1476 and Tech Design, we've decided to implement lazy subcommand groups on Kedro and Kedro Viz. This ticket is for the implementation on viz

Context

• Full proposal: [spike] Improve Kedro CLI startup time kedro#1476 (comment)

Possible Implementation

• Prototype: Refactor CLI with lazy subcommands and deferring imports #1920

Checklist

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