Refactor to support API prefixed Model example I/O files

[Malikbadmus]

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Description

This PR refactors Ersilia to support the handling of model example input and output files, ensuring backward compatibility with the previously used input.csv and output.csv filenames. It introduces changes to accommodate the new file naming convention with a run_ prefix (e.g., run_input.csv, run_output.csv), while still maintaining support for models that use the old naming convention.

This is part of the ongoing effort to support multiple APIs within Ersilia models and provide flexibility for future extensions.

Changes to be made

• Added support for run_input.csv and run_output.csv alongside the existing input.csv and output.csv.
• Updated PREDEFINED_EXAMPLE_FILES in default.py to include the new file naming conventions.
• Updated Dockerfile to copy both run_input.csv and run_output.csv during the build process, ensuring they are available in the container for model inference.
• Modified _write_api_schema to handle the new example files (run_input.csv and run_output.csv) in addition to the old files.
• Ensured that older models using the previous input.csv and output.csv files continue to function without modification, while working towards renaming the files to include run prefix in model repositories.

Status

Ongoing

To do

Related to #74

[DhanshreeA]

Thanks @Malikbadmus I think we can safely take the plunge into renaming everything and keeping just the new version.

[Malikbadmus]

Noted, @DhanshreeA. I will proceed with renaming the example files in the model repositories