* clean and improve docstrings in orm
* fix typos found with codespell
* rely on the Environment class docstring instead of doc content (and
therefore move part of the doc inside the class docstring)
closesodoo/odoo#102969
X-original-commit: 8250cd4b210005d223a4cdb8afa4014425ca6fa3
Related: odoo/documentation#2803
Signed-off-by: Victor Feyens (vfe) <vfe@odoo.com>