Embed executables in API JSON

[MikeMcQuaid]

• Avoid fetching executables.txt as a separate API artefact.
• Keep which-formula data generated from active formula JSON.
• Let internal API packages carry executable metadata.

---

• Have you followed the guidelines in our Contributing document?
• Have you checked to ensure there aren't other open Pull Requests for the same change?
• Have you added an explanation of what your changes do and why you'd like us to include them? Performance claims (e.g. "this is faster") must include Hyperfine benchmarks.
• Have you written new tests (excluding integration tests) for your changes? Here's an example.
• Have you successfully run brew lgtm (style, typechecking and tests) with your changes locally?

---

• AI was used to generate or assist with generating this PR. Please specify below how you used AI to help you, and what steps you have taken to manually verify the changes. Non-maintainers may only have one AI-assisted/generated PR open at a time.

OpenAI Codex 5.5 xhigh with local review, tweaks and testing.

---

[Copilot]

Pull request overview

Removes the dedicated internal/executables.txt download path and instead embeds per-formula executable lists in the formula/internal API JSON. The client-side cache file is regenerated from that JSON whenever update-report writes name/alias lookups, and brew which-formula/brew exec rely on brew update --auto-update to refresh it rather than performing their own curl.

Changes:

• Add executables to FormulaStruct and write it into per-formula JSON and internal packages.<tag>.json from ExecutablesDB data committed in the tap.
• Add Homebrew::API.write_executables_file! and call it from API::Formula.write_names_and_aliases / API::Internal.write_formula_names_and_aliases to regenerate internal/executables.txt from JSON.
• Drop the dedicated curl + homebrew.commandnotfound fetch path from update.sh/which-formula.sh (now ensure_executables_file just relies on auto-update).

Reviewed changes

Copilot reviewed 15 out of 15 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
Library/Homebrew/api.rb	New write_executables_file! writing internal/executables.txt from formula JSON.
Library/Homebrew/api/formula.rb	Call write_executables_file! after writing formula names/aliases.
Library/Homebrew/api/internal.rb	Same call from the internal-API path.
Library/Homebrew/api/formula_struct.rb	Add executables field to FormulaStruct.
Library/Homebrew/dev-cmd/generate-formula-api.rb	Load ExecutablesDB and inject executables into generated formula hashes.
Library/Homebrew/dev-cmd/generate-internal-api.rb	Same injection for internal packages JSON.
Library/Homebrew/executables_db.rb	New to_hash accessor for read-only consumers.
Library/Homebrew/cmd/update.sh	Remove conditional fetch of internal/executables.txt.
Library/Homebrew/cmd/which-formula.sh	Replace download_and_cache_executables_file with ensure_executables_file that triggers brew update --auto-update.
Library/Homebrew/cmd/exec.sh	Update caller to ensure_executables_file.
Library/Homebrew/test/api/*	Add coverage for executables field and write_executables_file!.
Library/Homebrew/test/dev-cmd/generate-*-api_spec.rb	Verify generator embeds executables read from ExecutablesDB.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.