Remove Percival from AMPL examples

[arnavk23]

@dpo @tmigot
AmplNLReader does not support the linear API that Percival's SlackModel requires. Only Ipopt is now used for AMPL problems in the benchmark examples.
Fixes #172

[Copilot]

Pull request overview

Updates the AMPL benchmarking example to only use solvers supported by AmplNLReader, removing the unsupported Percival/SlackModel path from the example workflow.

Changes:

• Removes Percival from the AMPL benchmark example imports.
• Removes the Percival solver entry so AMPL benchmarks run only with Ipopt.
• Adds a note explaining why Percival is excluded.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[arnavk23]

@tmigot Made the changes

SolverBenchmark.jl> julia --project=examples examples/bmark_ampl.jl
[ Info: running solver ipopt_lm
[ Info:          Solver             Name    nvar    ncon           status    iter      Time      f(x)      Dual    Primal  

******************************************************************************
This program contains Ipopt, a library for large-scale nonlinear optimization.
 Ipopt is released as open source code under the Eclipse Public License (EPL).
         For more information visit https://github.com/coin-or/Ipopt
******************************************************************************

[ Info:        ipopt_lm         brownden       4       0      first_order      16   5.8e-01   8.6e+04   8.7e-07   0.0e+00
[ Info:        ipopt_lm          genrose     500       0      first_order    1202   9.9e+00   1.0e+00   5.7e-06   0.0e+00
[ Info:        ipopt_lm            hs006       2       1      first_order       9   1.5e-01   4.6e-21   5.4e-11   7.1e-10
[ Info:        ipopt_lm            hs009       2       1      first_order       6   8.0e-03  -5.0e-01   7.4e-07   2.8e-14
[ Info:        ipopt_lm            hs033       3       2      first_order      12   1.0e-02  -4.6e+00   1.9e-06   3.4e-12
[ Info:        ipopt_lm             hs10       2       1      first_order      11   1.5e-02  -1.0e+00   6.7e-07   6.1e-09
[ Info:        ipopt_lm             hs11       2       1      first_order       6   1.1e-02  -8.5e+00   1.4e-07   8.7e-10
[ Info:        ipopt_lm             hs14       2       2      first_order       5   1.3e-02   1.4e+00   8.0e-11   9.1e-11
[ Info:        ipopt_lm              hs5       2       0      first_order       6   1.3e-02  -1.9e+00   3.6e-08   0.0e+00
[ Info:        ipopt_lm              hs6       2       1      first_order       9   1.2e-02   4.6e-21   5.4e-11   7.1e-10
[ Info:        ipopt_lm          rosenbr       2       0      first_order      42   9.8e-02   1.2e-14   8.3e-07   0.0e+00
[ Info: running solver ipopt
[ Info:          Solver             Name    nvar    ncon           status    iter      Time      f(x)      Dual    Primal  
[ Info:           ipopt         brownden       4       0      first_order       7   2.3e-01   8.6e+04   2.0e-07   0.0e+00
[ Info:           ipopt          genrose     500       0      first_order     361   7.1e-01   1.0e+00   4.1e-12   0.0e+00
[ Info:           ipopt            hs006       2       1      first_order       5   7.0e-03   0.0e+00   0.0e+00   0.0e+00
[ Info:           ipopt            hs009       2       1      first_order       3   6.0e-03  -5.0e-01   1.2e-11   2.3e-13
[ Info:           ipopt            hs033       3       2      first_order      10   1.1e-02  -4.6e+00   6.4e-08   2.7e-08
[ Info:           ipopt             hs10       2       1      first_order      11   5.0e-03  -1.0e+00   1.1e-08   1.4e-08
[ Info:           ipopt             hs11       2       1      first_order       7   7.0e-03  -8.5e+00   9.3e-10   1.4e-10
[ Info:           ipopt             hs14       2       2      first_order       6   8.0e-03   1.4e+00   2.2e-08   4.2e-09
[ Info:           ipopt              hs5       2       0      first_order       7   7.0e-03  -1.9e+00   3.3e-09   0.0e+00
[ Info:           ipopt              hs6       2       1      first_order       5   7.0e-03   0.0e+00   0.0e+00   0.0e+00
[ Info:           ipopt          rosenbr       2       0      first_order      21   2.1e-02   3.7e-21   1.7e-10   0.0e+00

[tmigot]

@dpo What do you think of this solution?

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 86.19%. Comparing base (4c0fcd2) to head (df98861).
⚠️ Report is 41 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #202      +/-   ##
==========================================
+ Coverage   76.71%   86.19%   +9.48%     
==========================================
  Files          12       10       -2     
  Lines         292      297       +5     
==========================================
+ Hits          224      256      +32     
+ Misses         68       41      -27     

☔ 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.