[clang-tidy] New check: bugprone-redundant-adjacent-find-check

Here is suggestion to add check to detects redundant end iterator checks after `std::adjacent_find`. When `std::adjacent_find` returns an iterator `it` that is not equal to `end()`, it is guaranteed that `std::next(it) != end()` is also true. A subsequent check for `std::next(it) != end()` is therefore redundant and should be removed.

**Non-compliant example:**
```cpp
auto it = std::adjacent_find(v.begin(), v.end(), pred);
if (it != v.end()) {
auto next_it = std::next(it);
if (next_it != v.end()) { // ALWAYS true - completely redundant
process(it, next_it);
}
}
```

**Compliant example:**
```cpp
auto it = std::adjacent_find(v.begin(), v.end(), pred);
if (it != v.end()) {
auto next_it = std::next(it);
process(it, next_it);
}
```

Start at the clang-tidy entry point and compare existing bugprone checks to understand how a new check is structured. Use the adjacent_find examples in this issue to define the redundant next-iterator condition; done means the check diagnoses that condition and leaves the compliant example unchanged.

Written by the indexing model from the issue text.