When running adnt run [app], the tool should automatically check the locally installed Rust toolchain version.
If the version is below the minimum required by the application, the user should be notified and prompted to upgrade.

Acceptance criteria:

• Detect current Rust toolchain version (rustc --version).
• Compare it against the minimum version defined by the application (e.g., in config or metadata).
• If outdated, display a clear message and propose an automatic upgrade (e.g., via rustup update).
• Continue execution only if the toolchain meets requirements.
• Add tests in CI to ensure version checking works.

Deliverables:

• Implementation
• Documentation update
• CI validation