The prior .gitignore only covered `scripts/_import_one_off_*.py`,
`scripts/_smoke_*.py`, and `tsconfig.tsbuildinfo`. This session
created scripts with other prefixes (_import_splits_, _patch_) and
a tsconfig.tsbuildinfo.bak that leaked through.
Added:
- scripts/_import_splits_*.py
- scripts/_patch_*.py
- tsconfig.tsbuildinfo.bak
Now all session-local helpers stay out of git.