Debian packages lag behind upstream. rustup gives a current toolchain
with minimal profile plus clippy and rustfmt.

Assisted-by: GLM-5.1 via pi

diff --git a/.ramekin/Dockerfile b/.ramekin/Dockerfile
index d948044..19ffc0a 100644
--- a/.ramekin/Dockerfile
+++ b/.ramekin/Dockerfile
@@ -1,10 +1,10 @@
 FROM ramekin-agent
 RUN apt-get update && apt-get install -y --no-install-recommends \
     bc \
-    cargo \
+    curl \
     grcov \
     jq \
-    rustc \
-    rustfmt \
     && rm -rf /var/lib/apt/lists/*
+RUN curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y --profile minimal --component clippy,rustfmt
+ENV PATH="/root/.cargo/bin:${PATH}"
 ENV RANGER_DEFAULT_BACKLOG=quire