Kernel-prove the classical Euler brick witness

[DomTheDeveloper]

Result

Proves directly that the classical cuboid

(44, 117, 240)

is an Euler brick, with exact integer face diagonals

125, 244, 267.

The branch also derives the existential theorem that a three-dimensional Euler brick exists.

Verification

The focused gate rejects holes and trust shortcuts, compiles the registered proof module, and audits both exported theorem footprints.

Keep draft until the exact current-toolchain gate is green.

[github-actions]

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