feat: add `needs_project` property

[mr-cal]

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Two things:

1. Refactors the LifecycleCommands classes in a slightly more organized way without changing any existing commands. This is required for snapcraft to define its own Pack command with minimal duplicated code (https://github.com/canonical/snapcraft/pull/4794)
2. Add a needs_project property, which can determine if a project needs to be loaded based on the provided arguments.

Fixes https://github.com/canonical/snapcraft/issues/4769 (CRAFT-2861)

[mr-cal]

Force-pushing so I can rebase