devops: add noarch support to meta.yaml

[mxschmitt]

This PR modifies our conda package configuration to use noarch: python in our meta.yaml. This change will help us distribute a single package that works across all Python versions (>=3.9 as specified in our requirements) instead of creating separate packages for each Python version.

Key changes:

• Added noarch: python to meta.yaml build configuration
• Updated CI workflow to use Python 3.12 for building (the build Python version becomes less relevant with noarch. Align it tho between out test and publish workflows)
• Added explicit miniconda-version: latest to ensure consistent builds (align between test/publish workflows)

Background:
Previously, our conda packages were being built specifically for each Python version (e.g., py39, py312, py313), which made distribution and maintenance more complex. By switching to noarch: python, we rely on the Python version requirements specified in meta.yaml (python >=3.9) to handle compatibility, while producing a single package that works across all supported Python versions.

Fixes #2740

[bskottke]

This happend after your merge:

C:\Users\KA1962
(py312f-test) λ conda update playwright
Retrieving notices: done
Channels:

• microsoft
• conda-forge
• defaults
  Platform: win-64
  Collecting package metadata (repodata.json): done
  Solving environment: done

Package Plan ##

environment location: C:\Progs\miniconda3\envs\py312f-test

added / updated specs:
- playwright

The following packages will be downloaded:

package                    |            build
---------------------------|-----------------
certifi-2025.1.31          |     pyhd8ed1ab_0         159 KB  conda-forge
------------------------------------------------------------
                                       Total:         159 KB

The following packages will be UPDATED:

certifi 2024.12.14-pyhd8ed1ab_0 --> 2025.1.31-pyhd8ed1ab_0

Proceed ([y]/n)? y

Downloading and Extracting Packages:

Preparing transaction: done
Verifying transaction: done
Executing transaction: done

C:\Users\KA1962
(py312f-test) λ conda update --all
Channels:

• microsoft
• conda-forge
• defaults
  Platform: win-64
  Collecting package metadata (repodata.json): done
  Solving environment: done

All requested packages already installed.

C:\Users\KA1962
(py312f-test) λ conda list playwright
packages in environment at C:\Progs\miniconda3\envs\py312f-test:

Name Version Build Channel
playwright 1.47.0 py312_0 microsoft
pytest-playwright 0.7.0 pyhe2000d9_0 microsoft

still the old version

[mxschmitt]

This requires a new Playwright release, e.g. v1.51.0 in order to include that change.