1- Add GitHub actions

[vvvieira]

This PR:

• Adds two unit-test jobs with varying dependencies
• Adds a coverage report generation and combine stage
• Adds a stage to leave a sticky comment on the PR with the coverage results

This CI setup is intended to run on a single stage to avoid having to upload images to storage (and thus, incur in extra billing). However, it uses GitHub Actions cache which has a generous limit to improve build speed. Subsequent pipelines on the same image take around 2 minutes to run.

[Copilot]

Pull Request Overview

This PR introduces a GitHub Actions workflow to automate CI tasks including Docker image building and testing.

• Adds a CI pipeline workflow configuration.
• Implements multi-stage jobs for Docker build and test execution.

Files not reviewed (1)

• Dockerfile: Language not supported

[github-actions]

🧪 Coverage Report

Name                                            Stmts   Miss Branch BrPart  Cover   Missing
-------------------------------------------------------------------------------------------
src/simulib/__init__.py                             0      0      0      0   100%
src/simulib/entities/__init__.py                    4      0      0      0   100%
src/simulib/entities/dynamic.py                   114      7     12      2    93%   63->62, 167-168, 173-176, 249
src/simulib/entities/steadystate.py                21      0      0      0   100%
src/simulib/io/__init__.py                         19      2      0      0    89%   17, 22
src/simulib/io/dynamic/__init__.py                 16      0      2      0   100%
src/simulib/io/dynamic/importers.py                12      0      0      0   100%
src/simulib/io/utils.py                             3      0      0      0   100%
src/simulib/methods/__init__.py                     8      1      0      0    88%   12
src/simulib/methods/dynamic/dfba/__init__.py       12      0      0      0   100%
src/simulib/methods/dynamic/dfba/entities.py       94      2      6      0    98%   144-145
src/simulib/methods/dynamic/dfba/simulator.py     123     10     38      5    89%   47->50, 71-72, 98-102, 135->134, 154-156, 158, 256
src/simulib/methods/dynamic/exceptions.py          10      0      0      0   100%
src/simulib/utils/__init__.py                       0      0      0      0   100%
src/simulib/utils/expression.py                    85     20     30      1    73%   63-66, 105-116, 120, 124-133
-------------------------------------------------------------------------------------------
TOTAL                                             521     42     88      8    90%

[jpfon]

this is awesome! thanks @vvvieira
LGTM!

[jpfon]

LGTM