Don't invalidate lockfile on all changes of the pyproject.toml

[ruben-arts]

Checks

• [X] I have checked that this issue has not already been reported.

• [X] I have confirmed this bug exists on the latest version of pixi, using pixi --version.

Reproducible example

pixi init test --pyproject
cd test
pixi add python
# Creates lockfile correctly
pixi install # invalidated lockfile as we create the lockfile before we add python to the pyproject.toml, invalidating the hash of the toml. 
pixi task add bla echo bla
pixi install # Again invalidated as we added something to the pyproject.toml, but this is unrelated to the metadata we need for the solve. 

Issue description

We unsatisfy the lockfile on the hash of the pyproject.toml in an pypi-dependency. This is however often not required as the change might have nothing to do with the meta data.

Expected behavior

pixi add x
pixi install

Should only create the lockfile once

pixi task add bla echo bla

Or any none metadata related change should not invalidate the lockfile.

[tdejager]

Hmm, I think we may need to add that this should only hold for the main pyproject.toml and not any other pyproject.toml that we may reference.

[ruben-arts]

not any other pyproject.toml that we may reference.

That counts for the pixi commands but changing [tool.x] tables in subpackages also invalidate those packages. Which is also not correct.