Pin Zed v1.16.1 and the gpui-component baseline to immutable revisions, align the Rust toolchain requirement, and regenerate Cargo.lock.
This is a dependency checkpoint only: application API migration and Nebula product patches remain for isolated follow-up commits, so gpui-shell is not yet expected to compile.
Committed with --no-verify because the repository line-count hook rejects generated Cargo.lock growth above 2500 lines; staged diff checks and locked offline metadata validation pass.
kuddev
10ed04c656