Pyproject2conda

Changed

- Allow `overrides` for all options.
- `overrides` override environment options.

Removed

- Removed comments based (` p2c: ...`) support. Specify changes with
`tool.pyproject2conda.dependencies` table only. This greatly simplifies the
code, and has become the primary way to use the `pyproject2conda`.

Added

- Added [PEP 735](https://peps.python.org/pep-0735/) support. This includes
adding option `--group` to the cli, and `groups` key to
`tools.pyproject2conda.envs....` tables. There is also an option
`--extra-or-group` (or `extras_or_groups` in pyproject.toml) that will first
try to find dependencies from "extras" and then from "groups".

Changed

- Passing no extras to an environment now defaults to no added extras or groups.
Old behavior (to default to the extra with the same name as the environment)
was lead to complications with support of `dependency-groups`. Explicitly pass
the extra or group if to get the old behavior.
- `default_envs` now passed the environment name as `extras_or_groups`.
Therefore, if the name of the environment is an extra, it will be used.
Otherwise, it will be from a group of that name.

- Removed option `--base/--no-base`. Replaced with `--skip-package`. Default is
to include package dependencies. Pass `--skip-package` (or
`skip_package = true` in `pyproject.toml`) to skip package dependencies.

Added

- Can now access "build-system.requires" as an extra. This can be useful for
creating isolated environments to build a package.

Changed

- Can now specify `pip` as a conda dependency. This is needed for cases that
there are no pip dependencies in the environment, but you want it there for
installing local packages. This may be the case if using `conda-lock` on an
environment. Note that, much like python is always first in the dependency
list, pip is always last.

Added

- Can now specify conda changes using `tool.pyproject2conda.dependencies` table.
This is an alternative to using ` p2c:` comments.
- Refactored code. Split `parser` to `requirements` and `overrides`. Also
cleaned up the parsing logic to hopefully make future changes simpler.

Added

- Default is now to remove whitespace from dependencies. For example, the
dependency `module > 0.1` will become `module>0.1`. To override this
behaviour, pass the option `--no-remove-whitespace`.
- Now supports python version `>3.8,<=3.12`
- Can now specify `extras = false` in pyprojec.toml to skip any extras. The
default (`extras = true`) is the same as `extras = [env_name]` where
`env_name` is the name of the environment (e.g.,
`tool.pyproject2conda.envs.env_name`).

Added

- Added option to either raise error, or print message for environments with no
dependencies.

Changed

- pyproject2conda now works with `pyproject.toml` files with no dependencies.