This PR changes all `lean-toolchain` to use relative toolchain paths
instead of `lean4` and `lean4-stage0` identifiers, which removes the
need for manually linking toolchains via Elan.
After this PR, at least Elan 4.2.0 and 0.0.224 of the Lean VS Code
extension will be needed to edit core.
Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
This PR introduces a simple script that adjusts module headers in a
package for use of the module system, without further minimizing import
or annotation use.
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Co-authored-by: Kim Morrison <477956+kim-em@users.noreply.github.com>