bindings/python: add float32 bindings

[Sergim96]

Description

This PR adds core single-precision Python bindings exposed through the new
pinocchio.float32 module.

The change:

• adds a Python binding context using float as its scalar type;
• exposes numpy.float32 as pinocchio.float32.ScalarType;
• makes sample-model factories and affected model/frame algorithms use the
  active binding scalar instead of hard-coded double types;
• adds float32-specific exp, log, and utils helpers;
• registers native submodules under pinocchio.float32.*;
• fixes the scalar-generic model, frame, LCABA, and ADMM implementations needed
  by the bindings;
• integrates the extension into the CMake build and installation, controlled by
  BUILD_PYTHON_BINDINGS_WITH_FLOAT32_SUPPORT;
• adds the extension to the stub-generation dependencies;
• adds regression coverage for RNEA, sample models, model and frame algorithms,
  helper dtypes, submodule imports, LCABA, ADMM, and collision-enabled sample
  geometry.

This allows Pinocchio's core kinematics and dynamics APIs to operate directly
on single-precision NumPy arrays.

Geometry and collision objects retain their existing double-backed
representation. File parsers, parallel algorithms, and reachable-workspace
helpers remain available only through the main module.

Checklist

• I have run pre-commit run --all-files or pixi run lint
• I have performed a self-review of my own code
• I have commented my code where necessary
• I have made corresponding changes to the doxygen documentation
• I have added tests that prove my fix or feature works
• I have updated the CHANGELOG or added the "no changelog" label if it's a CI-related issue
• I have updated the README credits section

[github-actions]

👋 Hi,
This is a reminder message to assign an extra build label to this Pull Request if needed.
By default, this PR will be build with minimal build options (URDF support and Python bindings)
The possible extra labels are:

• build_collision (build Pinocchio with coal support)
• build_casadi (build Pinocchio with CasADi support)
• build_autodiff (build Pinocchio with CppAD support)
• build_codegen (build Pinocchio with CppADCodeGen support)
• build_extra (build Pinocchio with extra algorithms)
• build_mpfr (build Pinocchio with Boost.Multiprecision support)
• build_sdf (build Pinocchio with SDF parser)
• build_accelerate (build Pinocchio with APPLE Accelerate framework support)
• build_all (build Pinocchio with ALL the options stated above)

Thanks.
The Pinocchio development team.

[jcarpent]

Thanks @Sergim96 for this PR.
Could you split it into two parts:

• a first PR where you have fixed the bindings (adding context, Scalar, etc.).
• a second one for support of float32?

Thanks in advance,
Best,
Justin