feat(linter): implement Phase 1 linter automation and docs

- Add .clang-tidy (analyzer + selected bugprone) and .clang-format (LLVM, 4-space, 100 cols)
- Enhance scripts/run-linter.sh to use compile_commands.json when available
- Add scripts/setup-hooks.sh pre-commit (format enforcement; advisory tidy)
- Update azure-pipelines.yml to export compile_commands and run clang-tidy -p build
- Fill docs/linter-setup.md and docs/coding-standards.md for Phase 1
- Add minimal tests in tests/test_main.cpp to ensure CI executes
- Rewrite README with Phase 1 workflow

scripts/run-linter.sh

@@ -12,7 +12,7 @@ if ! command -v clang-tidy &> /dev/null; then
 fi
 
 # 尋找所有 C++ 檔案
-CPP_FILES=$(find src tests -name "*.cpp" -o -name "*.h" 2>/dev/null)
+CPP_FILES=$(find src tests -type f \( -name "*.cpp" -o -name "*.cxx" -o -name "*.cc" -o -name "*.c++" -o -name "*.h" -o -name "*.hpp" -o -name "*.hxx" \) 2>/dev/null)
 
 if [ -z "$CPP_FILES" ]; then
     echo "No C++ files found."
@@ -23,7 +23,17 @@ echo "Found files:"
 echo "$CPP_FILES"
 echo
 
-# 執行 clang-tidy
-echo "$CPP_FILES" | xargs clang-tidy --config-file=.clang-tidy
+# 若存在 compile_commands.json，則使用 -p 指向 build 目錄以提高精準度
+TIDY_CMD_BASE=(clang-tidy --config-file=.clang-tidy)
+if [ -f "build/compile_commands.json" ]; then
+    echo "Detected build/compile_commands.json; using -p build"
+    TIDY_CMD_BASE+=( -p build )
+else
+    echo "No compile_commands.json detected. For better results, run:"
+    echo "  mkdir -p build && cd build && cmake .. -DCMAKE_EXPORT_COMPILE_COMMANDS=ON && cd -"
+fi
 
-echo "Linter check completed."
+# 執行 clang-tidy（保持 Phase 1：僅回報，不讓流程失敗）
+echo "$CPP_FILES" | xargs -r "${TIDY_CMD_BASE[@]}"
+
+echo "Linter check completed."