Record compiler warning output in dice example

[DerekCorniello]

Updates the golden output for dice_simulation to include the new W0300 unused-binding diagnostics emitted by the paired compiler.

This keeps the shared examples runner deterministic while the compiler warning catalog is introduced.

This PR is intentionally ready for review (not a draft).

[greptile-apps]

Greptile Summary

Updates the dice simulation golden output to include unused-binding compiler warnings and adds support for selecting a paired compiler branch through a PR label.

• Records the two W0300 diagnostics in the expected output.
• Resolves and validates an optional paired-compiler:<branch> label before checking out the compiler.
• Continues to use the compiler’s main branch when no paired branch is selected.

Confidence Score: 5/5

The PR appears safe to merge.

No blocking failure remains.

Important Files Changed

Filename	Overview
.github/workflows/examples.yml	Adds validated PR-label-based compiler ref selection while retaining main as the default.
examples/dice_simulation/expected_output.txt	Updates the exact-output fixture with the compiler’s two W0300 unused-binding diagnostics.

_{Reviews (3): Last reviewed commit: "Document paired compiler validation" | Re-trigger Greptile}