Update the C-like style check to an ARM-compatible clang-format version

@ann0see arbeitet bereits daran.

Seit 15.9.2026.

## Summary

Update the C-like coding-style check to use a newer `clang-format` version on the Ubuntu 24.04 ARM runner.

The current workflow configures `DoozyX/clang-format-lint-action` with `clangFormatVersion: 14`. Version 14 was selected for Ubuntu 22.04 LTS. The job now uses `ubuntu-24.04-arm`.

## Rationale

The Docker action copies bundled `clang-format` executables into its image. The ARM runner cannot rely on a bundled executable unless that executable supports ARM64.

Ubuntu 24.04 provides an ARM64-native `clang-format-18` package. This is a newer supported version and is an ARM-compatible path for the workflow.

## Affected area

- `.github/workflows/coding-style-check.yml`
- `check-c-like-style` job

## Required changes

Replace or adapt the formatter invocation so that the ARM job installs and uses the Ubuntu 24.04 ARM64 `clang-format-18` package. Do not depend on an architecture-specific formatter binary from the current action unless ARM64 support is verified.

Review and apply any formatting changes that version 18 requires.

## Acceptance criteria

- The C-like style job runs successfully on `ubuntu-24.04-arm`.
- The job uses `clang-format` version 18 or another explicitly verified newer ARM64-compatible version.
- The job checks `.cpp`, `.h`, and `.mm` files with the existing repository style configuration.
- Required formatting updates are included or tracked before the version change is enabled.

## Research

Ubuntu's package index lists `clang-format-18` for Ubuntu 24.04 (`noble`) on `arm64`.

- https://packages.ubuntu.com/clang-format
- https://launchpad.net/ubuntu/noble/arm64/clang-format/1:18.0-59~exp2

## Backlinks

- Requested by @ann0see in https://github.com/jamulussoftware/jamulus/pull/3954#issuecomment-5679589906
- Related PR: https://github.com/jamulussoftware/jamulus/pull/3954