Copper 1.2.4: faster project scaffolding

v1.2.4 - 2026-10-04

This patch releases cargo-cunew 1.2.4 for Copper 1.2.

Fixes

• Project generation selects each Copper dependency's latest stable, non-yanked version within the 1.2 release line. All generated Copper requirements use ~. This fixes the unavailable cu29-build = "~1.2.3" requirement after selective runtime patch releases.
• Installing the scaffold tool builds 78 packages on Linux, down from 269 in the previous published tool's current dependency graph. Bundled templates use Liquid directly, and registry queries use synchronous HTTPS with Rustls. Git repository initialization uses the installed git command or can be skipped with --no-vcs.
• CI builds and runs both generated templates against crates.io on release-branch changes, after GitHub releases, and daily. A separate check enforces a 100-package installer budget and rejects the removed heavy dependencies.

Upgrading

Run cargo install cargo-cunew --version '~1.2.4' --force. Generate your project with cargo cunew hello_copper, enter the generated hello_copper directory, and run cargo run.

For an existing generated project that fails to resolve cu29-build, change its build dependency to cu29-build = "~1.2.1". Keep cu29 = "~1.2.3"; the runtime and other Copper crates retain their existing compatible versions.