SP-38: Add new CLI commands for singe node operations

[Buqeta (Buqeta)]

Description

Adds new CLI commands for single-node operations against the Pacman public API:

• config nodes create --packageKey ... [--body <json> | -f <file>] [--validate] [--json] — creates a staging node. --validate calls the validate-only endpoint (no persistence) and exits with a success log if the payload is valid; otherwise fails.
• config nodes update --packageKey ... --nodeKey ... [--body <json> | -f <file>] [--validate] [--json] — updates a staging node. --validate behaves the same as above.
• config nodes delete --packageKey ... --nodeKey ... [--force] — archives a staging node.

Payload can be provided either inline via --body or from a file via -f/--file (mutually exclusive; one is required for create/update).

Relevant links

• Jira: https://celonis.atlassian.net/browse/SP-38
• Pacman endpoints PR: https://github.com/celonis/pacman/pull/1647

Checklist

• I have self-reviewed this PR
• I have tested the change and proved that it works in different scenarios
• I have updated docs if needed

[sonarqubecloud]

Quality Gate failed

Failed conditions
60.6% Coverage on New Code (required ≥ 80%)

See analysis details on SonarQube Cloud

[Buqeta (Buqeta)]

Ignoring the coverage check, since it requires covering the transport files and the module.ts file, which doesn't make much sense.