CITATION.cff; README badges in series

[sshin23]

Per request: a CITATION.cff in NLPModels.jl's style — Sungho Shin as the author, the EPSR article as preferred-citation with DOI/volume matching the README's bibtex, v0.12.0 as the released version — and the README header rebuilt: logo gone, badge table gone, six badges in one series (license · docs stable · docs dev · CI · codecov · release). The tagline stays.

🤖 Generated with Claude Code

[codecov]

Welcome to Codecov 🎉

Once you merge this PR into your default branch, you're all set! Codecov will compare coverage reports and display results in all future pull requests.

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[github-actions]

Benchmark Results

Relative timing: current / main  (values < 1.0 are improvements)

================================================================================
  backend-instance-param          |      obj     cons     grad      jac     hess
================================================================================
  CUDA-OPF-case1354               |    0.998    0.972    0.998    0.991    0.987
  CUDA-OPF-case14                 |    1.000    0.982    0.998    0.989    0.985
  CUDA-OPF-case30000              |    1.010    0.973    0.993    0.989    0.995
  CUDA-chain-10                   |    0.994    0.991    0.992    1.012    0.991
  CUDA-chain-100                  |    0.991    0.998    0.992    1.006    0.991
  CUDA-chain-1000                 |    0.996    0.994    0.994    1.010    0.991
  CUDA-elec-10                    |    1.006    0.996    0.990    0.983    1.003
  CUDA-elec-100                   |    0.957    1.001    0.986    0.990    1.003
  CUDA-elec-1000                  |    1.026    0.998   20.211    0.991    0.902
  CUDA-rosenrock-1000             |    0.983    0.912    0.931    0.972    0.921
  CUDA-rosenrock-10000            |    1.105    0.911    0.914    0.938    0.918
  CUDA-rosenrock-100000           |    0.986    1.190    1.085    1.017    1.001
--------------------------------------------------------------------------------
  AMDGPU-OPF-case1354             |    1.009    1.030    1.012    1.023    1.076
  AMDGPU-OPF-case14               |    1.032    1.053    1.069    1.016    1.037
  AMDGPU-OPF-case30000            |    1.017    1.063    1.065    1.076    1.016
  AMDGPU-chain-10                 |    1.018    1.016    1.066    1.095    1.054
  AMDGPU-chain-100                |    1.034    1.054    1.017    1.092    0.967
  AMDGPU-chain-1000               |    1.040    1.020    0.999    1.065    1.073
  AMDGPU-elec-10                  |    1.038    1.055    1.015    1.074    1.028
  AMDGPU-elec-100                 |    1.014    1.030    1.061    1.094    1.092
  AMDGPU-elec-1000                |    1.040    1.056    0.966    1.076    0.939
  AMDGPU-rosenrock-1000           |    1.056    1.024    0.997    1.013    0.990
  AMDGPU-rosenrock-10000          |    1.058    1.043    1.008    1.026    1.029
  AMDGPU-rosenrock-100000         |    1.326    1.028    1.053    1.069    1.022
--------------------------------------------------------------------------------
  oneAPI-OPF-case1354             |    1.327    0.645    0.861    0.552    0.643
  oneAPI-OPF-case14               |    1.185    1.074    0.965    1.219    1.317
  oneAPI-OPF-case30000            |    1.345    0.748    1.010    1.159    1.106
  oneAPI-chain-10                 |    1.192    1.419    0.529    1.339    1.013
  oneAPI-chain-100                |    0.968    0.968    0.844    0.927    1.603
  oneAPI-chain-1000               |    1.286    1.111    0.836    0.846    0.918
  oneAPI-elec-10                  |    1.249    1.044    1.234    0.918    1.535
  oneAPI-elec-100                 |    1.405    0.812    0.867    1.276    1.076
  oneAPI-elec-1000                |    1.029    1.053    0.933    1.008    0.993
  oneAPI-rosenrock-1000           |    1.026    1.028    0.853    1.402    0.618
  oneAPI-rosenrock-10000          |    1.090    1.252    1.538   10.305    1.095
  oneAPI-rosenrock-100000         |    2.412    0.114    0.632    1.381    1.160
--------------------------------------------------------------------------------
  nothing-OPF-case1354            |    0.947    0.924    0.952    1.013    0.613
  nothing-OPF-case14              |    0.982    0.942    0.995    1.007    0.867
  nothing-OPF-case30000           |    0.942    1.013    0.965    1.009    0.992
  nothing-chain-10                |    1.053    1.018    1.114    1.008    1.362
  nothing-chain-100               |    0.936    0.948    0.992    0.946    0.724
  nothing-chain-1000              |    0.972    1.000    0.986    1.091    1.442
  nothing-elec-10                 |    1.004    1.044    1.065    1.081    1.064
  nothing-elec-100                |    1.058    1.110    0.944    0.952    0.988
  nothing-elec-1000               |    0.998    1.170    0.937    1.002    1.019
  nothing-rosenrock-1000          |    1.000    1.058    1.001    0.995    0.922
  nothing-rosenrock-10000         |    1.057    0.991    1.061    0.962    5.521
  nothing-rosenrock-100000        |    0.946    0.947    0.998    0.993    0.865
================================================================================