[clang][Diagnostics] Add source range to uninitialized diagnostics (#65896)

Before:

```
array.cpp:319:10: note: read of uninitialized object is not allowed in a constant expression
  319 |    return aaa;
      |           ^
```

After:

```
array.cpp:319:10: note: read of uninitialized object is not allowed in a constant expression
  319 |    return aaa;
      |           ^~~
```