[Copilot]

All seven ARM64 build jobs failed with Exec format error when executing the bundled AMD64 DevPanel CLI. Native ARM runners lacked the execution support previously provided by AMD64 build hosts.

• Build configuration: Enable QEMU on ARM runners; retain the skip for native AMD64 builds.
• CLI installation: Restore unconditional installation and version verification, reverting the ARM64 omission workaround.
• Documentation: Clarify that published ARM64 images still require host AMD64 emulation to run the CLI. Correct runner labels to ubuntu-26.04 and ubuntu-26.04-arm.

[Copilot]

🟢 Approval recommended

The focused condition change matches the intended architecture handling, with no unresolved findings; native ARM execution remains unverified.

No open issues 🎉

What changed in this PR

Enables AMD64 emulation on ARM CI runners so builds can execute the bundled DevPanel CLI, while retaining the QEMU skip for native AMD64 builds.

Changes:

• Updates the shared build action to enable QEMU on ARM runners.
• Documents the host emulation requirement for ARM64 images and corrects runner labels.
• Records completed work and validation limitations in the task checklist.

File	Description
TODO.md	Records implementation progress and the native ARM validation limitation.
README.md	Clarifies CLI emulation requirements and runner configuration.
.github/​actions/​build-php-images/​action.yml	Enables QEMU on ARM runners while preserving the native AMD64 skip.

_{Review effort: Balanced}