Use MS devcontainer base, docker cp R/Python libs

Base on MS devcontainer Jammy image to match OpenSAFELY base image.

Install R/Python and their dependencies using the respective
requirements.txt from the `main` branch on github.
This file is not copied to the built docker action images so we cannot
copy it from their containers.

Use `docker cp` to copy the R/Python library files to the host filesystem
which avoids any of the previously seen issues with mounting a running
container.

However, these library directories don't contain any symlinks
(verified with `find . -type l`) so one of the major issues with
mounting is not of concern here so commented-out mount-based
alternative is provided here which has better performance than the
`docker cp` approach.

Author: Jongmassey

.devcontainer/devcontainer.json

@@ -2,13 +2,13 @@
 // README at: https://github.com/devcontainers/templates/tree/main/src/python
 {
     "name": "OpenSAFELY",
-    "image": "ghcr.io/opensafely-core/research-template:v0",
+    "image": "mcr.microsoft.com/devcontainers/base:ubuntu-22.04",
     // Features to add to the dev container. More info: https://containers.dev/features.
     "features": {
         "ghcr.io/devcontainers/features/docker-in-docker:2": {}
     },
-    "postCreateCommand": "/bin/bash /opt/devcontainer/postCreate.sh ${containerWorkspaceFolder}",
-    "postAttachCommand": "/bin/bash /opt/devcontainer/postAttach.sh",
+    "postCreateCommand": "/bin/bash .devcontainer/postCreate.sh",
+    "postAttachCommand": "/bin/bash .devcontainer/postAttach.sh",
     "forwardPorts": [
         8787
     ],
@@ -41,7 +41,7 @@
                 "files.autoSaveDelay": 1000,
                 "git.autofetch": true,
                 "python.analysis.extraPaths": [".devcontainer/ehrql-main/"],
-                "python.defaultInterpreterPath": "/opt/venv/bin/python",
+                "python.defaultInterpreterPath": "./venv/bin/python",
                 "python.terminal.activateEnvInCurrentTerminal": true,
                 "python.terminal.activateEnvironment": true,
                 "window.autoDetectColorScheme": true

.devcontainer/postAttach.sh

@@ -0,0 +1 @@
+opensafely launch rstudio -p 8787 &

.devcontainer/postCreate.sh

@@ -0,0 +1,45 @@
+#download and extract latest ehrql source
+wget https://github.com/opensafely-core/ehrql/archive/main.zip -P .devcontainer
+unzip -o .devcontainer/main.zip -d .devcontainer/
+rm .devcontainer/main.zip
+
+# install python and dependencies, set up virtualenv
+sudo apt update
+wget https://github.com/opensafely-core/python-docker/raw/refs/heads/main/v2/dependencies.txt -q -O - | sed 's/^#.*//' | sudo xargs apt-get install --yes --no-install-recommends
+pip install virtualenv opensafely
+python3 -m virtualenv .venv
+# copy the docker image virtualenv library to the local virtualenv.
+# this could alternatively be done with a bind mount (see below)
+rm  -rf .venv/lib
+docker container create --name python-v2 ghcr.io/opensafely-core/python:v2
+docker cp python-v2:/opt/venv/lib .venv/
+docker rm python-v2
+## bind mount version - faster and less disk space but we need to consider
+## implications for `docker pull`/`opensafely pull`
+## and what happens if container is stopped/restarted
+# rm  -rf .venv/lib/*
+# docker run -it -d --name python-v2 --rm ghcr.io/opensafely-core/python:v2 bash
+# mount=$(docker inspect python-v2 -f '{{.GraphDriver.Data.MergedDir}}')
+# mount --bind -o ro "$mount/opt/venv/lib" .venv/lib
+
+
+# install R and dependencies
+docker create --name r-v2 ghcr.io/opensafely-core/r:v2
+sudo docker cp r-v2:/etc/apt/sources.list.d/cran.list /etc/apt/sources.list.d/cran.list
+sudo docker cp r-v2:/etc/apt/trusted.gpg.d/cran_ubuntu_key.asc /etc/apt/trusted.gpg.d/cran_ubuntu_key.asc
+sudo apt update
+wget https://raw.githubusercontent.com/opensafely-core/r-docker/refs/heads/main/v2/dependencies.txt -q -O - | sed 's/^#.*//' | sudo xargs apt-get install --yes --no-install-recommends
+sudo docker cp r-v2:/usr/lib/R/etc/Rprofile.site /usr/lib/R/etc/Rprofile.site
+# copy image R library to local R library
+# this could alternatively be done with a bind mount (see below)
+docker create --name r-v2 --rm ghcr.io/opensafely-core/r:v2
+sudo docker cp r-v2:/usr/local/lib/R/site-library /usr/local/lib/R/
+sudo chown -R vscode:vscode /usr/local/lib/R/site-library/
+docker rm r-v2
+## bind mount version - faster and less disk space but we need to consider
+## implications for `docker pull`/`opensafely pull`
+## and what happens if container is stopped/restarted
+# docker rm r-v2
+# docker run -it -d --name r-v2 --rm ghcr.io/opensafely-core/r:v2 bash
+# mount=$(docker inspect r-v2 -f '{{.GraphDriver.Data.MergedDir}}')
+# sudo mount --bind -o ro "$mount/usr/local/lib/R/site-library" /usr/local/lib/R/