Add `project status` command to display project state and template info

[lex57ukr]

Goal

Provide a quick way to view the current project's state and its relationship to the upstream Keystone template.

Scope

• Display current project configuration details
• Show the source template name and repository
• Show the branch the template was synced from
• Check if a newer version of the Keystone template is available upstream

Outcome

Users can quickly assess their project's template status without manually inspecting configuration files, and know when a template update is available.

Notes

This command focuses on template version awareness, not local file modifications.

[lex57ukr]

Implement #116 first before working on this issue.