Improve KNITRO implementation

[eminyouskn]

Fixes # NA

Summary/Motivation:

This PR implements the improvements proposed in #3707 and establishes a new branch for further related enhancements.

Changes proposed in this PR:

• Reformatted long lines.
• Usage of bounds instead of lower and upper to extract variable bounds.
• Usage of to_bound_expression for bounds extraction of constraints.
• Enhace messages of the DeveloperError.

Legal Acknowledgement

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

1. I agree my contributions are submitted under the BSD license.
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.

[codecov]

Codecov Report

❌ Patch coverage is 63.15789% with 7 lines in your changes missing coverage. Please review.
✅ Project coverage is 89.23%. Comparing base (b58edfe) to head (f246238).
⚠️ Report is 6 commits behind head on main.

Files with missing lines	Patch %	Lines
pyomo/contrib/solver/solvers/knitro/engine.py	64.70%	6 Missing ⚠️
pyomo/contrib/solver/solvers/knitro/base.py	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3762      +/-   ##
==========================================
+ Coverage   89.05%   89.23%   +0.18%     
==========================================
  Files         907      907              
  Lines      104862   105536     +674     
==========================================
+ Hits        93382    94176     +794     
+ Misses      11480    11360     -120     

Flag	Coverage Δ
builders	29.20% <5.26%> (-0.01%)	⬇️
default	85.86% <63.15%> (?)
expensive	35.75% <5.26%> (?)
linux	86.69% <5.26%> (-2.13%)	⬇️
linux_other	86.69% <5.26%> (+0.18%)	⬆️
osx	82.82% <5.26%> (-0.01%)	⬇️
win	84.93% <5.26%> (-0.01%)	⬇️
win_other	84.93% <5.26%> (-0.01%)	⬇️

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[eminyouskn]

Just to note that this PR is ready.