Replace brew which-update

[MikeMcQuaid]

• Keep brew which-update as the CI-facing incremental command for command-not-found database entries.
• Remove the scheduled updater workflow and old bulk scan flags because core CI now updates touched formulae.
• Reuse executables_db.rb for versionless database writes and bottle metadata updates.
• Regenerate command docs, completions and Sorbet RBI for the new command interface.

@Rylan12 Have tried to minimise the changes from the existing code where possible to slim the diff here. It may be we decide to rearrange things a bit later but hopefully this helps make it easier to merge.

See also Homebrew/homebrew-core#281990
Fixes #20752
Closes #21790
Closes Homebrew/homebrew-core#272976

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OpenAI Codex 5.5 xhigh with manual tweaks, review and very many approach changes.

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[Copilot]

Pull request overview

This PR refactors brew which-update into an incremental, CI-oriented updater for the command-not-found executables database, shifting away from the previous scheduled bulk-update model and aligning updates with “touched formulae” in core CI.

Changes:

• Reworks brew which-update flags and behavior to support updating/removing specific formula entries, optionally from generated bottle JSON and/or a GitHub pull request’s changed formula list.
• Updates ExecutablesDB to support versionless DB reads/writes and to populate binaries from bottle metadata (manifest path_exec_files) with a tarball fallback.
• Regenerates manpage/docs/completions/Sorbet RBI and adds/updates tests for versionless DB compatibility and bottle JSON updates.

Reviewed changes

Copilot reviewed 10 out of 11 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
manpages/brew.1	Updates manpage options for the new which-update interface.
Library/Homebrew/test/dev-cmd/which-update_spec.rb	Adds an integration test for bottle JSON-driven updates and removals; adjusts typing sigil.
Library/Homebrew/test/cmd/which-formula_spec.rb	Adds coverage for versionless DB entries in which-formula.
Library/Homebrew/sorbet/rbi/dsl/homebrew/dev_cmd/which_update.rbi	Regenerates RBI for new CLI args.
Library/Homebrew/executables_db.rb	Implements versionless DB parsing/writing and new update sources (bottle JSON / bottle manifest).
Library/Homebrew/dev-cmd/which-update.rb	Replaces legacy bulk-scan flags with incremental inputs and optional PR-based formula detection; writes updated= to GITHUB_OUTPUT.
docs/Manpage.md	Mirrors the manpage option changes in docs.
completions/zsh/_brew	Updates zsh completions for the new flags.
completions/fish/brew.fish	Updates fish completions for the new flags.
completions/bash/brew	Updates bash completions for the new flags.
.github/workflows/command-not-found-db-update.yml	Removes the scheduled workflow for bulk updates.

Files not reviewed (1)

• Library/Homebrew/sorbet/rbi/dsl/homebrew/dev_cmd/which_update.rbi: Language not supported

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[Rylan12]

Looks good! Let's merge, and can clean up later. I think there's lots of stuff that can be ripped out of here, I pointed a few out below.

Also, if I remember correctly, lots of the executables_db.rb code is just to create a nice, human-readable changelog for the commit message. But since we're not committing anymore, we probably don't need that nice changelog anymore

[Copilot]

Pull request overview

Copilot reviewed 10 out of 11 changed files in this pull request and generated 3 comments.

Files not reviewed (1)

• Library/Homebrew/sorbet/rbi/dsl/homebrew/dev_cmd/which_update.rbi: Language not supported