Linux Rust target missing

Doctor did not find the Linux x64 GNU Rust target. This is a warning for template/native plugin development, not a requirement for a prebuilt-template export without plugins.

#Common causes

• x86_64-unknown-linux-gnu is absent from the active Rust toolchain.

#Fixes

• Run rustup target add x86_64-unknown-linux-gnu.

• Code: ARA-EXP-LNX-005 (slot 8035)

• Constant: export::LNX_005

• Reported by: ara-export