Omit redundant File header in SyntaxError collection output

[avenet]

Summary

Follow-up to #14899 / #14994: during collection, when the FILE:LINE:COLUMN crash line is appended, drop the now-redundant stdlib File "...", line N header from the E-block. Keep the source and caret lines, and leave the no-column fallback and runtime --tb=* paths unchanged.

Depends on #14899 (this branch is based on it; once that merges, this PR's diff shrinks to the collection-path change alone).

Before:

E     File "test_broken.py", line 1
E       def broken(:
E                  ^
E   SyntaxError: invalid syntax
test_broken.py:1:12: SyntaxError: invalid syntax

After:

E       def broken(:
E                  ^
E   SyntaxError: invalid syntax
test_broken.py:1:12: SyntaxError: invalid syntax

Test plan

• Collection of def broken(: shows caret + file:line:col, no File header

• IndentationError collection likewise omits the header

• SyntaxError without offset still keeps the File header

• Runtime --tb=long still shows the File header

• testing/code + collection/terminal/reports/junitxml (784 passed)

• pre-commit run on touched files

• Include documentation when adding new features.

• Include new tests or update existing tests when applicable.

• Allow maintainers to push and squash when merging my commits.

• Closes Redundant File ..., line N block in SyntaxError output #14994

• If AI agents were used, they are credited in Co-authored-by commit trailers.

• Create a new changelog file in the changelog directory (14994.improvement.rst).

• Add yourself to AUTHORS in alphabetical order.

[SemTiOne]

Thanks, but why are my commits included here?

[RonnyPfannschmidt]

this is a stacked pr jsut without a github pr stack feautre being used