Loading the V2 code as a separate project to allow them to coexist.

[Paultagoras]

Summary

Checklist

Delete items not relevant to your PR:

• Unit and integration tests covering the common scenarios were added
• A human-readable description of the changes was provided to include in CHANGELOG
• For significant changes, documentation in https://github.com/ClickHouse/clickhouse-docs was updated with further explanations or tutorials

[sonarqubecloud]

Quality Gate failed

Failed conditions
3 Security Hotspots
0.0% Coverage on New Code (required ≥ 80%)
10.0% Duplication on New Code (required ≤ 3%)
E Reliability Rating on New Code (required ≥ A)

See analysis details on SonarCloud

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