[FEATURE]: Let DependencyLoader.load_dependency return MaybeSourceContainer

[JCZuurmond]

Is there an existing issue for this?

• I have searched the existing issues

Problem statement

Let DependencyLoader.load_dependency return MaybeSourceContainer similarly to the other Maybe objects:

class MaybeSourceContainer:
    """A source container or failures while loading the source containers."""

    source_container: SourceContainer | None = None
    """The source container if successfully loaded."""

    problems: list[DependencyProblem] = dataclassess.field(default_factory=list)
    """The problems while loading the dependency into a source container unsuccesfully."""

    def __post_init__(self):
        if not self.source_container and not self.problems:
            raise ValueError(f"Source container OR problems should be given: {self}.")
        if self.source_container and self.problems
            raise ValueError(f"Source container OR problems should be given: {self}.")

Motivation

Localizes the surfacing and handling errors close to where the sources are loaded so that the problems can be reused where applicable.

Proposed Solution

See above

Additional Context

No response