Add clang-tools v22 support

[Copilot]

clang-22 is not shipped in any standard Ubuntu apt repository — it's only available via apt.llvm.org (llvm-toolchain-noble-22, etc.). This adds v22 support using the llvm.sh installation path already established in Dockerfile.all.

Changes

• Dockerfile: Added USE_LLVM_REPO=false build arg. When true, runs llvm.sh $CLANG_VERSION to register the apt.llvm.org repo before the standard apt-get install clang-format-$N clang-tidy-$N. No impact on existing targets.

• docker-bake.hcl: Added "22" to the default group and a new target using ubuntu:noble + USE_LLVM_REPO="true":

  args = {
    BASE_IMAGE    = "ubuntu:noble"
    CLANG_VERSION = "22"
    USE_LLVM_REPO = "true"
  }

• Dockerfile.all: Added 22 to both the llvm.sh-installed CLANG_VERSIONS list and the integrity-check CLANG_VERSIONS list.

• README.md: Added 22 to the supported tags list.

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Support clang-tools v22</issue_title>
<issue_description>https://github.com/llvm/llvm-project/releases/tag/llvmorg-22.1.0

Originally posted by @shenxianpeng in #105</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Support clang-tools v22 #114

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
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0.0% Coverage on New Code
0.0% Duplication on New Code

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