Add config option to disable optional checks

### Describe the Bug

https://mypy.readthedocs.io/en/stable/command_line.html#no-strict-optional

pyright has a bunch of optional-specific error codes, for people who are migrating from codebases without null-safety

ideal implementation is unclear, maybe the easiest way is to treat None as Any in is_subset_eq, but IDK the downstream implications of this.

### Sandbox Link

_No response_

### (Only applicable for extension issues) IDE Information

_No response_

Start by reading the optional-check handling and the is_subset_eq logic mentioned in the issue, then compare the requested behavior with mypy's no-strict-optional setting and Pyright's optional-specific error codes. The work is done when there is a configuration option to disable these checks and its downstream type-checking behavior is validated.

Written by the indexing model from the issue text.