v1.11.0

• Created the EasyFEA.FEM.Operators module, gathering the element-level operators that integrate a form over the Gauss points (issue #43).
  • Bilinear: UV, GradUGradV, GradU_A_GradV, LinearizedElasticity, MassAlongNormal, and the beam operators BeamBending, BeamShear, BeamStiffness, BeamMass.
  • Linear: V.
  • NonLinear: SecondPiolaKirchhoffStressTensor, KelvinVoigtDamping, FollowingPressure.
  • Refactored the simulations to assemble their element matrices through these operators.
• Introduced finite-strain viscosity and active stress in hyperelasticity (issue #42).
  • Kelvin-Voigt viscosity material.eta (large-strain Σ_visco = η·Ė), delivered through NonLinear.KelvinVoigtDamping, which returns both the damping matrix and the configuration tangent so the gap is closed without touching the time-scheme coefficient mechanism.
  • Fiber active stress material.active_stress along a direction registered with material.Set_active_stress_vec.
• Added the CardiacElastoDynamics example (MonoVentricular.py): a passive + active hyperelastic left-ventricle simulation reproducing Benchmark 1: monoventricular mechanics of the cardiac elastodynamics benchmark (Comput. Methods Appl. Mech. Engrg.), with analytic and cardiac_benchmark_toolkit (vtu) fiber/sheet sources (issue #42).
• Refactored Construct_local_matrix_system and made HyperElasticState operate on a groupElem; the velocity is now passed explicitly to KelvinVoigtDamping instead of being stored on the state (issue #44).
• Added FeArray reduction methods and an integrate helper, and fixed a FeArray.broadcast ambiguity on per-element tensors via tensor_ndim.
• Fixed a shared mutable-default-dictionary bug in the Save_Iter functions that leaked iteration keys across calls and across simulations in the same process.
• Fixed bugs in phaseField._Calc_Sigma_e_pg, in the LinearizedElasticity examples, in groupElem._Get_Mapping / Get_pointsInElem (local connectivity), and in the Mesher MPI partitioning (snapshot connectivity before gmsh.partition).
• Fixed an mpi4py deadlock on plain python and a petsc4py double-initialization warning.
• Updated Mesher.Mesh_Import_mesh to reconstruct physical groups from gmsh entities and to accept a meshOrder argument; renamed wedge to penta in MeshIO.DICT_ELEMTYPE_TO_ENSIGHT.
• Documentation: added an Operators section to the FEM API and a "from element operators to the global system" section to the solve-pipeline guide; improved the introduction docstrings of every simulation; referenced CardiacElastoDynamics in the docs and READMEs.

Full Changelog: v1.10.1...v1.11.0