`match_docstring_end` matches too much, making I002 introduce a syntax error

[dscorbett]

Summary

When multiple string-only statements appear at the top of a module, class, or function definition, only the first is the docstring, but match_docstring_end matches them all. That makes the fix for missing-required-import (I002) insert required imports after all the string-only statements, not immediately after the docstring. That is usually harmless but it introduces a syntax error when the required import is a future import. Example:

$ cat >i002.py <<'# EOF'
"docstring"
"not a docstring"
print(f"{__doc__=}")
# EOF

$ python i002.py
__doc__='docstring'

$ ruff --isolated check --config 'lint.isort.required-imports=["from __future__ import annotations"]' i002.py --select I002 --fix
Found 1 error (1 fixed, 0 remaining).

$ cat i002.py
"docstring"
"not a docstring"
from __future__ import annotations
print(f"{__doc__=}")

$ python i002.py 2>&1 | tail -n 1
SyntaxError: from __future__ imports must occur at the beginning of the file

Version

ruff 0.12.2 (9bee837 2025-07-03)