Add a simpler way to wrap existing flowsheets for FlowsheetRunner

[dangunter]

Fixes #1771

Summary/Motivation:

See issue

Changes proposed in this PR:

• add simple_wrap.py with a decorator function fi_main
• import fi_main at structfs subpackage level so from idaes.core.util.structfs import fi_main will work
• add some utility functions in fsrunner to find and run the wrapped methods (as well as find the older-style global flowsheet objects)

Legal Acknowledgement

By contributing to this software project, I agree to the following terms and conditions for my contribution:

1. I agree my contributions are submitted under the license terms described in the LICENSE.txt file at the top level of this directory.
2. I represent I am authorized to make the contributions and grant the license. If my employer has rights to intellectual property that includes these contributions, I represent that I have received permission to make contributions and grant the required license on behalf of that employer.

[dangunter]

@CopyDemon @sspoon

This is the simplified wrapper code. It pretty much does what we talked about.

Sheng, note that there are a few new functions at the bottom of fsrunner.py that can be used to detect whether the module has a global flowsheet object (like previously), or uses this simplified wrapper function, or neither. See the tests with the word "wrapped" in their names in test_fsrunner.py

[dangunter]

Example usage (from the docs)

from idaes.core.util.structfs import fi_main

@fi_main
def my_main_function(some, args, keyword=None): # can take any arguments
    # build the flowsheet -> model
    model = build_flowsheet()
    # initialize the flowsheet
    # solve the flowsheet -> solve_result
    solve_result = solve_flowsheet()

    # **Important!**: return the model and solve result as a tuple
    return model, solve_result

[codecov]

Codecov Report

❌ Patch coverage is 87.69231% with 8 lines in your changes missing coverage. Please review.
✅ Project coverage is 73.82%. Comparing base (886bb73) to head (c1a74eb).

Files with missing lines	Patch %	Lines
idaes/core/util/structfs/fsrunner.py	70.37%	4 Missing and 4 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1772      +/-   ##
==========================================
- Coverage   73.82%   73.82%   -0.01%     
==========================================
  Files         419      421       +2     
  Lines       66274    66331      +57     
  Branches    11133    11139       +6     
==========================================
+ Hits        48927    48968      +41     
- Misses      14810    14818       +8     
- Partials     2537     2545       +8     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.