formula_creator: add deny network for cabal and zig

[cho-m]

Continuing work on extending deny_network_access!.

For Cabal, using std_cabal_v2_args as that includes resolver arguments (e.g. backjumps) which are needed during fetch

• texmath: add deny_network_access! homebrew-core#301832

For Zig, can default to plain --fetch (skip lazy deps) and switch to --fetch=all only when lazy deps are needed:

• formulae(zig dependents): add deny_network_access! and fetch homebrew-core#301864

Also invert the list as shorter to list remaining modes. Still working on some issues with crystal (Homebrew/homebrew-core#301831) and zig (Homebrew/homebrew-core#301796) before we can update formulae.

Was also trying out Ruby bundle cache but working through some errors.

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[Copilot]

🟡 Changes recommended

The inverted mode filter lacks regression coverage for all five excluded modes.

Once you've addressed the issues Copilot identified, you can request another Copilot review.

Pull request overview

Extends generated Cabal formulae to separate dependency fetching from offline installation.

Changes:

• Enables network denial for Cabal formulae.
• Adds Cabal’s download-only fetch phase.
• Simplifies mode filtering and updates tests.

File summaries

File	Description
Library/Homebrew/formula_creator.rb	Updates Cabal formula generation and network rules.
Library/Homebrew/test/formula_creator_spec.rb	Tests generated Cabal fetch behavior.

Review details

• Files reviewed: 2/2 changed files
• Comments generated: 1
• Review effort level: Balanced

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[MikeMcQuaid]

Thanks, love these!