The MT serial-reset bridge now declares its Rust scalar projection before
executing the diagnostic branch. This keeps the declaration ordering valid for
the C90-oriented compiler flags used by the native test builds while leaving
the Rust-owned policy and callback sequence unchanged.
Test Plan:
- `ulimit -v 41943040; CARGO_BUILD_JOBS=1 make -j1` -- passed without the
new mixed-declaration warning.
- `git diff --cached --check` -- passed.
ddidderr
17b0f36767