Add support for passing --project <PROJECT> to deployment list

[m-abdelwahab]

Summary

Adds project selection support to railway deployment list via --project <PROJECT>, matching the service-scoped command pattern used elsewhere in the CLI.

Why

deployment list previously only worked from the linked project, even though related commands such as logs/restart/redeploy can target another project through --project plus --environment.

Changes

• Adds -p, --project <PROJECT> to railway deployment list.
• Routes deployment listing through resolve_service_context so project, environment, and service resolution stay consistent.
• Adds exact project ID/name resolution for shared service context commands, with ambiguity errors for duplicate project names.
• Preserves the previous case-insensitive service-name behavior when resolving explicit services.
• Adds a CLI parser regression test for deployment list --project ... --environment ... --service ....

Validation

• cargo test cli_tests
• cargo test --no-run
• cargo run -- deployment list --help

Release

Minor: exposes a new CLI flag for an existing command.