Upgrade clang-format patch version from v18.1.3 to v18.1.8 as developer's changes fail on CI

[Pranav Rathi (pranavrth)]

No description provided.

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[Copilot]

Pull request overview

This PR updates the Docker-based CI infrastructure to use a newer version of clang-format 18 from the official LLVM repository. The changes address issues where developer's code formatting changes were failing in CI, likely due to version inconsistencies between the Ubuntu default package and what developers were using locally.

Changes:

• Added LLVM apt repository to the Dockerfile to get a more recent clang-format 18 version
• Added version debugging output to style checking scripts
• Incremented the CI cache tag to force rebuilding Docker images with the new configuration

Reviewed changes

Copilot reviewed 8 out of 10 changed files in this pull request and generated 3 comments.

File	Description
packaging/tools/Dockerfile	Adds LLVM repository configuration and installs clang-format-18 from it, with version verification
packaging/tools/style-format.sh	Adds debug output to print clang-format version before validation
packaging/tools/run-style-check.sh	Adds debug output to print clang-format version
.semaphore/semaphore.yml	Increments cache tag from 7 to 8 to invalidate cached Docker images

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[Pratyush Ranjan (PratRanj07)]

LGTM