[colinjlacy]

Introduces the standalone Go-based rc CLI as a shared entry point for Runtime Conditions tooling.

• Adds Cobra commands for help, version reporting, shell completion, profile generation, and binding validation.
• Includes go-rc-profiler as a direct dependency, calling its exported APIs internally. Users need a Go toolchain but no separate profiler installation.
• Supports both rc profile generate and rc profile go generate, with native Cobra flags, typed options, cancellation checks, consistent errors, and atomic file output.
• Adds build tooling that embeds release metadata and a checksum-verified core schema.
• Adds implementation and distribution planning, component locks, and staging utilities.
• Adds unit tests and GitHub Actions CI across Linux/macOS amd64/arm64, including isolated executable smoke tests.
  Local race tests, static checks, and smoke tests pass. Homebrew/APT publishing, binding orchestration, and additional language add-ons remain planned.

[itvi-1234]

Looks good :)