build(deps): bump mypy from 1.19.1 to 2.0.0 in /requirements - #74

Starting April 2026, the CodeQL Action will skip computing file coverage information on pull requests to improve analysis performance. File coverage information will still be computed on non-PR analyses. To opt out of this change, set the `CODEQL_ACTION_FILE_COVERAGE_ON_PRS` environment variable to `true`.