[clang-tidy] readability-redundant-parentheses deletes reference NTTP uses with no parentheses

`readability-redundant-parentheses` diagnoses a use of a reference non-type template parameter as redundant parentheses, even when no parentheses are written. Applying the fix-it deletes the parameter name and produces invalid code.

Reproducer:

```c++
int value = 0;

template
int &get() {
return R;
}

int &use() {
return get();
}
```

```sh
clang-tidy --checks="-*,readability-redundant-parentheses" test.cpp -- -std=c++17
```

```text
test.cpp:5:10: warning: redundant parentheses around expression [readability-redundant-parentheses]
5 | return R;
| ^
```

Applying the fix with `--fix` changes the return statement to:

```c++
return ;
```

The original program compiles, but the fixed version fails because `get` must return a value.

In the instantiated AST, the reference template argument is represented by a `SubstNonTypeTemplateParmExpr` containing a synthetic `ParenExpr`. Both parenthesis locations point to the `R` token. The check matches this synthetic node and removes the token as though it were a written parenthesis.

The check should avoid diagnosing or removing synthetic parentheses that do not correspond to parentheses in the source.

Reproduced on LLVM 24.0.0git.

Start with the clang-tidy readability-redundant-parentheses check and reproduce the issue using the shown test.cpp and clang-tidy command. Trace how the instantiated AST represents the reference non-type template parameter, then add coverage showing that synthetic parentheses are not diagnosed or removed and that the original code remains valid after --fix.

Written by the indexing model from the issue text.