[clang-tools-extra] [clang-tidy] Add check performance-lost-std-move (PR #139525)

[via cfe-commits]

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+.. title:: clang-tidy - performance-lost-std-move
+
+performance-lost-std-move
+=========================
+
+Warns if copy constructor is used instead of ``std::move()`` and suggests a fix.
+It honours cycles, lambdas, and unspecified call order in compound expressions.
+
+.. code-block:: c++
+
+   void f(X);
+
+   void g(X x) {
+     f(x);  // warning: Could be std::move() [performance-lost-std-move]
+   }
+
+It finds the last local variable usage, and if it is a copy, emits a warning.
+The check is based on pure AST matching and doesn't take into account any
+data flow information. Thus, it doesn't catch assign-after-copy cases.
+
+Also it does notice variable references "behind the scenes":
+
+.. code-block:: c++
+
+   void f(X);
+
+   void g(X x) {
+     auto &y = x;
+     f(x);  // does not emit a warning
+     y.f();  // because x is still used via y
+   }
+
+If you want to ignore assigns to reference variables, set :option:`StrictMode`
+to `true`.
+
+
+Options
+-------
+
+.. option:: StrictMode
+
+   A variable ``X`` can be referenced by another variable ``R``. In this case
+   the last variable usage might be not from ``X``, but from ``R``. It is quite
+   difficult to find in a large function, so if the plugin sees some ``R``
+   references ``X``, then it will not emit a warning for ``X`` not to provoke
+   false positive. If you're sure that such references don't extend ``X``
+   lifetime and ready to handle possible false positives, then set `StrictMode`
+   to `true`. Default is `false`.
----------------
EugeneZelenko wrote:

```suggestion
   lifetime and ready to handle possible false positives, then set
   :option:`StrictMode` to `true`. Default is `false`.
```

https://github.com/llvm/llvm-project/pull/139525