Add standalone single-module profile smoke test

[RonaldHensbergen]

Summary

Adds tests/test_standalone_module_profile.py, a generic smoke test that
discovers every module.yaml under modules/ (and modules-experimental/,
if present) and validates it in isolation.

For each module, the test builds a throwaway single-module Profile
referencing only that module — no sibling modules, no dependsOn, no
contract bindings supplied by another module — and runs it through
cli.validator.validate_profile.

Modules with a required consumes entry (e.g. Superset's
metadataDatabase, Dagster's run-storage) can't resolve that binding
standalone, so E030/E041/E042 diagnostics are expected and allowlisted.
Any other diagnostic code (E001, E010, E011, E020, E021, E022,
...) fails the test, since it indicates a genuine problem with the module's
own definition — invalid YAML, a schema violation in module.yaml itself,
or a malformed consumes/provides entry.

Testing

• python -m unittest tests.test_standalone_module_profile -v
• python -m unittest discover -s tests -p "test_*.py" -v (full suite, 556 tests, all pass)
• make lint