Apply a few clang-tidy suggestions manually

The workflow action fails linking, probably because it changes the
hpp and cpp at different times, who knows

.clang-tidy

@@ -37,6 +37,7 @@ Checks: >
           -cppcoreguidelines-pro-type-const-cast,
           -cppcoreguidelines-pro-type-member-init,
           -cppcoreguidelines-pro-type-vararg,
+          -cppcoreguidelines-use-default-member-init,
         misc-*,
           -misc-confusable-identifiers,
           -misc-const-correctness,

ql/math/matrixutilities/householder.cpp

@@ -21,7 +21,7 @@
 
 namespace QuantLib {
 
-    HouseholderTransformation::HouseholderTransformation(const Array v)
+    HouseholderTransformation::HouseholderTransformation(Array v)
     : v_(std::move(v)) {}
 
 
@@ -41,7 +41,7 @@ namespace QuantLib {
         return m;
     }
 
-    HouseholderReflection::HouseholderReflection(const Array e)
+    HouseholderReflection::HouseholderReflection(Array e)
     : e_(std::move(e)) {}
 
     Array HouseholderReflection::reflectionVector(const Array& a) const {

ql/math/matrixutilities/householder.hpp

@@ -29,30 +29,30 @@
 namespace QuantLib {
 
     /*! References:
-     	 https://en.wikipedia.org/wiki/Householder_transformation
+        https://en.wikipedia.org/wiki/Householder_transformation
     */
 
     class HouseholderTransformation  {
       public:
-    	explicit HouseholderTransformation(const Array v);
+        explicit HouseholderTransformation(Array v);
 
         Matrix getMatrix() const;
-    	Array operator()(const Array& x) const;
+        Array operator()(const Array& x) const;
 
       private:
-    	const Array v_;
+        const Array v_;
     };
 
 
     class HouseholderReflection {
       public:
-        explicit HouseholderReflection(const Array e);
+        explicit HouseholderReflection(Array e);
 
         Array operator()(const Array& a) const;
-    	Array reflectionVector(const Array& a) const;
+        Array reflectionVector(const Array& a) const;
 
       private:
-    	const Array e_;
+        const Array e_;
     };
 }
 

ql/methods/finitedifferences/operators/fdmwienerop.cpp

@@ -32,11 +32,11 @@
 namespace QuantLib {
 
     FdmWienerOp::FdmWienerOp(
-        ext::shared_ptr<FdmMesher> mesher,
+        const ext::shared_ptr<FdmMesher>& mesher,
         ext::shared_ptr<YieldTermStructure> rTS,
-        Array lambdas)
-        : rTS_(rTS),
-          r_(0.0) {
+        const Array& lambdas)
+    : rTS_(std::move(rTS)),
+      r_(0.0) {
 
         QL_REQUIRE(mesher->layout()->dim().size() == lambdas.size(),
             "mesher and lambdas need to be of the same dimension");

ql/methods/finitedifferences/operators/fdmwienerop.hpp

@@ -35,9 +35,9 @@ namespace QuantLib {
     class FdmWienerOp : public FdmLinearOpComposite {
       public:
         FdmWienerOp(
-            ext::shared_ptr<FdmMesher> mesher,
+            const ext::shared_ptr<FdmMesher>& mesher,
             ext::shared_ptr<YieldTermStructure> rTS,
-            Array lambdas);
+            const Array& lambdas);
 
         Size size() const override;
         void setTime(Time t1, Time t2) override;