ci: make cpp-linter tidy-only and use pip-installed clang-tidy

Drop clang-format from the cpp-linter job (pre-commit already runs the pinned
clang-format hook on every PR) and point --version at the setup-python bin dir
so clang-tidy resolves to the pip-installed 22.1.8 instead of a system
clang-tidy-22. Adds a temporary probe to exercise CI; will be dropped.

Author: LuciferYang

.github/workflows/cpp-linter.yml

@@ -49,9 +49,8 @@ jobs:
       SCCACHE_DIR: ${{ github.workspace }}/.sccache
       SCCACHE_CACHE_SIZE: "2G"
       CPP_LINTER_VERSION: "1.13.0"
-      # clang-format is kept in sync with .pre-commit-config.yaml; clang-tidy is
-      # pinned separately because that version is not published on PyPI.
-      CLANG_FORMAT_VERSION: "22.1.5"
+      # clang-format is handled by the pre-commit workflow; cpp-linter runs
+      # clang-tidy only.
       CLANG_TIDY_VERSION: "22.1.8"
     steps:
       - name: Checkout iceberg-cpp
@@ -104,7 +103,7 @@ jobs:
         if: github.event_name == 'pull_request'
         run: |
           python -m pip install --upgrade pip
-          python -m pip install "cpp-linter==${CPP_LINTER_VERSION}" "clang-format==${CLANG_FORMAT_VERSION}" "clang-tidy==${CLANG_TIDY_VERSION}"
+          python -m pip install "cpp-linter==${CPP_LINTER_VERSION}" "clang-tidy==${CLANG_TIDY_VERSION}"
       - name: Run cpp-linter
         id: linter
         if: github.event_name == 'pull_request'
@@ -114,9 +113,9 @@ jobs:
         # need '-fno-builtin-std-forward_like', see https://github.com/llvm/llvm-project/issues/101614
         run: |
           cpp-linter \
-            --style=file \
+            --style='' \
             --tidy-checks='' \
-            --version="${CLANG_FORMAT_VERSION%%.*}" \
+            --version="${pythonLocation}/bin" \
             --files-changed-only=true \
             --lines-changed-only=true \
             --thread-comments=true \

src/iceberg/temp_linter_probe.cc

@@ -0,0 +1,17 @@
+// TEMP verification file — will be dropped before merge.
+// Confirms cpp-linter runs clang-tidy with the pip-installed binary
+// (via --version=${pythonLocation}/bin) after dropping clang-format.
+namespace iceberg {
+
+class TempLinterProbe {
+ public:
+  int* probe() {
+    int* ptr = 0;  // modernize-use-nullptr should flag this
+    return ptr;
+  }
+
+ private:
+  int badMember;  // readability-identifier-naming: missing trailing underscore
+};
+
+}  // namespace iceberg