Support passing additional template variables to the cFS backend. Refs #106.

[ivanperez-keera]

Extend cfs command and the cFS backend to accept and use an optional JSON file containing additional variables to expand in the template, as prescribed in the solution proposed for #106.

[ivanperez-keera]

Change Manager: Verified that:

• Solution is implemented:
  • The code proposed compiles and passes all tests. Details:
    • Build log:
      • https://github.com/nasa/ogma/actions/runs/13129204043/job/36631018742
      • https://github.com/nasa/ogma/actions/runs/13129204050/job/36631018723
    • Build log archives:
      • logs_33898708833.zip
      • logs_33898708846.zip
  • The solution proposed produces the expected result. Details:
    The following dockerfile first checks that passing the additional extra variables files does not affect the result unless the variable is mentioned in the template, by comparing the result to a run without passing any extra vars. It later adds a file with a custom variable, and then passes an extra template variable using the new flag, after which it prints the message "Success":

    FROM ubuntu:focal
    
    ENV DEBIAN_FRONTEND=noninteractive
    RUN apt-get update
    
    RUN apt-get install --yes \
          curl g++ gcc git libgmp3-dev libz-dev make pkg-config
    
    RUN mkdir -p $HOME/.local/bin
    ENV PATH=$PATH:/root/.local/bin/
    
    RUN curl https://downloads.haskell.org/~ghcup/0.1.17.7/x86_64-linux-ghcup-0.1.17.7 -o $HOME/.local/bin/ghcup
    RUN chmod a+x $HOME/.local/bin/ghcup
    
    ENV PATH=$PATH:/root/.ghcup/bin/
    RUN ghcup install ghc 9.10
    RUN ghcup install cabal 3.12
    RUN ghcup set ghc 9.10.1
    RUN cabal update
    
    SHELL ["/bin/bash", "-c"]
    CMD git clone $REPO \
        && cd $NAME \
        && git checkout $COMMIT \
        && cabal install ogma-cli:ogma \
        && ogma cfs --variable-file ogma-cli/examples/cfs-variables --variable-db ogma-cli/examples/cfs-variable-db --app-target-dir original --handlers-file ogma-cli/examples/cfs-handlers \
        && cp -r ogma-core/templates/copilot-cfs custom \
        && find custom -iname '.gitignore' -delete \
        && echo '{ "message": "Success" }' >> template-vars \
        && ogma cfs --variable-file ogma-cli/examples/cfs-variables --variable-db ogma-cli/examples/cfs-variable-db --app-target-dir new --handlers-file ogma-cli/examples/cfs-handlers \
            --app-template-dir custom --template-vars template-vars \
        && diff -rq original new \
        && echo '{{message}}' >> custom/fsw/result \
        && rm -rf new \
        && ogma cfs --variable-file ogma-cli/examples/cfs-variables --variable-db ogma-cli/examples/cfs-variable-db --app-target-dir new --handlers-file ogma-cli/examples/cfs-handlers \
            --app-template-dir custom --template-vars template-vars \
        && cat new/fsw/result

    Command (substitute variables based on new path after merge):

    $ docker run -e "REPO=https://github.com/ivanperez-keera/ogma" -e "NAME=ogma" -e "COMMIT=08b63d220710f42bcea1e95c1087ae89fce4fad6" -it ogma-verify-106
    

• Implementation is documented. Details:
  All new top-level definitions are documented. The README is updated to also document new arguments, and how they can be used in custom templates.
• Change history is clear.
• Commit messages are clear.
• Changelogs are updated.
• Examples are updated. Details:
  Updates not needed; change does not affect the examples.
• Author is internal or has provided signed CLA.
• Required version bumps are evaluated. Details:
  Bump needed; the change affects the API of ogma-core.