Move opam install to postCreate

Author: nojaf

.devcontainer/Dockerfile

@@ -2,9 +2,9 @@ FROM mcr.microsoft.com/devcontainers/rust:1-1-bookworm
 LABEL org.opencontainers.image.authors="Christoph Knittel <ck@cca.io>"
 LABEL org.opencontainers.image.description="Docker image for ReScript development."
 
-RUN apt update && apt install -y --no-install-recommends opam musl-tools python-is-python3
-
-# OCaml
-# RUN opam init -y --bare --disable-sandboxing git+https://github.com/rescript-lang/opam-repository
-# RUN opam switch create 5.2.0 --packages ocaml-option-static
-# RUN opam install -y dune cppo=1.6.9 js_of_ocaml-compiler=5.8.1 ocamlformat=0.26.2 ounit2=2.2.7 reanalyze=2.25.1
+RUN apt-get update && export DEBIAN_FRONTEND=noninteractive \
+    && apt-get -y install --no-install-recommends \
+    opam \
+    musl-tools \
+    python-is-python3 \
+    && rm -rf /var/lib/apt/lists/*

.devcontainer/postCreate.sh

@@ -1,11 +1,8 @@
 #!/bin/sh
 
-# Opam stuff post install
+# Install dev dependencies from OPAM
 opam init -y --bare --disable-sandboxing git+https://github.com/rescript-lang/opam-repository
 opam switch create 5.2.0 --packages ocaml-option-static
-opam install -y dune cppo=1.6.9 js_of_ocaml-compiler=5.8.1 ocamlformat=0.26.2 ounit2=2.2.7 reanalyze=2.25.1
-
-# Install dev dependencies from OPAM
 opam install . --deps-only -y
 
 # For IDE support, install the OCaml language server