fix(commit0): count errored report instances

[onatozmenn]

Fixes #493

Commit0 builds its report from output.jsonl, but runner errors are written to output_errors.jsonl. Those runs disappear from the submitted and error counts.

This reads the sibling error file, ignores IDs with a completed final result, and deduplicates repeated errors. The report now includes submitted and incomplete IDs and counts like GAIA.

Tested with the Commit0 evaluator, report summary, and metrics suites (46 passed), plus Ruff, pycodestyle, and Pyright. The regression test also fails on current main.

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[onatozmenn]

Hi maintainers — both the Pre-commit checks and Run tests workflows are awaiting maintainer approval on this fork PR. Could someone approve the current runs so CI can execute? I’ll address any failures once results are available.