Add note about meson-python and installation path

New people that want to use Meson for building Python extensions most
probably will read Python module docs first. Direct them to meson-python
and suggest to set `python.install_env=auto`.

docs/markdown/Builtin-options.md

@@ -408,7 +408,8 @@ interpreter directly, even if it is a venv. Setting to `venv` will instead use
 the paths for the virtualenv the python found installation comes from (or fail
 if it is not a virtualenv).  Setting to `auto` will check if the found
 installation is a virtualenv, and use `venv` or `system` as appropriate (but
-never `prefix`). This option is mutually exclusive with the `platlibdir`/`purelibdir`.
+never `prefix`). Note that Conda environments are treated as `system`.
+This option is mutually exclusive with the `platlibdir`/`purelibdir`.
 
 For backwards compatibility purposes, the default `install_env` is `prefix`.
 

docs/markdown/Python-module.md

@@ -12,6 +12,15 @@ authors:
 This module provides support for finding and building extensions against
 python installations, be they python 2 or 3.
 
+If you want to build and package Python extension modules using tools
+compatible with [PEP-517](https://peps.python.org/pep-0517/), check out
+[meson-python](https://mesonbuild.com/meson-python/index.html).
+
+If you are building Python extension modules against a Python interpreter
+located in a venv or Conda environment, you probably want to set
+`python.install_venv=auto`;
+see [Python module options](Builtin-options.md#python-module) for details.
+
 *Added 0.46.0*
 
 ## Functions