Didn't flag "I'm was giving" as incorrect

## Description

I typed this sentence "I'm was giving it a second shot.", and it didn't flag it as incorrect. Obviously, the word "was" be deleted.

Reproduce the sentence “I'm was giving it a second shot.” in Harper and trace how this grammar pattern is analyzed. Confirm the expected behavior from the report: the checker should flag the sentence and identify “was” for deletion. No specific source file or test is named, so locating the relevant rule and test coverage will be part of the work.

Written by the indexing model from the issue text.