contributions: allow --user with --maintainer-report-csv

[p-linnane]

brew contributions --maintainer-report-csv=YEAR-QUARTER scans every Maintainer listed at the end of that quarter. That is right for the quarterly governance report, but it is a lot of Git and GitHub work when you only need to check one person, and --user conflicted with --maintainer-report-csv so there was no way to narrow it.

Dropping that conflict lets --maintainer-report-csv=YEAR-QUARTER --user=USER emit the full report schema for only the requested quarter-end Maintainers. The filter runs before the tenure and contribution scans, usernames match case-insensitively, emails resolve to GitHub logins as elsewhere in the command, and Lead Maintainer status and the historical quarter semantics are unchanged.

Requesting someone who was not a Maintainer at the end of the quarter errors and names only the unmatched users. Filtered reports are written to brew-contributions-FROM-to-TO-USER.csv so they cannot overwrite a full report. Behavior with --user omitted is unchanged.

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• I did not use AI/LLM to create this PR, or I disclosed the tool/model below and reviewed its output; I did not attribute commits to AI and will answer maintainer questions and review comments myself without AI/LLM.

Claude Code (Opus 5) drafted the implementation and tests; I reviewed the diff, verified the new tests fail without the change and pass with it, and ran brew lgtm + targeted specs.

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[Copilot]

Pull request overview

This pull request updates brew contributions to allow --user to be used together with --maintainer-report-csv, enabling generation of a maintainer-report CSV for a specific subset of quarter-end Maintainers (rather than scanning all Maintainers for that quarter).

Changes:

• Removes the --maintainer-report-csv/--user conflict and adds filtering logic so --user limits the report to matching quarter-end Maintainers (including email-to-login resolution).
• Adjusts maintainer-report CSV output filenames to include the filtered user set to avoid overwriting the unfiltered report.
• Updates help/manpage/docs and shell completions, and adds RSpec coverage for filtering/error cases.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
manpages/brew.1	Documents the updated --user semantics with --maintainer-report-csv and the filtered-report filename behavior.
Library/Homebrew/test/dev-cmd/contributions_spec.rb	Adds specs covering maintainer-report user filtering, email resolution errors, and filtered output filename behavior.
Library/Homebrew/dev-cmd/contributions.rb	Implements allowing --user with --maintainer-report-csv, filters quarter-end Maintainers, and changes the report output filename when filtered.
docs/Manpage.md	Mirrors manpage/help updates for contributions options and filtered maintainer-report output naming.
completions/zsh/_brew	Updates zsh completions to reflect that --user is allowed with --maintainer-report-csv and updates option descriptions.
completions/fish/brew.fish	Updates fish completions descriptions to match the new --user/maintainer-report behavior and filename wording.

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[MikeMcQuaid]

Good idea!