Add support for comments in .bazelignore files

### Description of the feature request:

It would be nice if it would be possible to use comments in `.bazelignore` files, e.g.

```
ree/acceptance_tests/ # has its own MODULE.bazel file
third_party # ignore third-party folder
```

Currently, line 1 is interpreted by Bazel as "ignore folder that is `named ree/acceptance_tests/ # has its own MODULE.bazel file`", i.e. it considers the comment as a part of the path name to ignore.

Since `#` works as a comment in `BUILD(.build)`, `WORKSPACE(.bazel)`, `MODULE.bazel`, `.bazelrc` etc. it would be nice if it would also work for `.bazelignore` files

### What underlying problem are you trying to solve with this feature?

Be able to write down some description why something is ignored

### Which operating system are you running Bazel on?

macOS, Windows, Ubuntu

### What is the output of `bazel info release`?

8.5.0

Start by locating Bazel’s .bazelignore reader and any existing tests for ignore-file parsing. Confirm how inline # text is currently treated, then add coverage for the examples so comments are accepted while the intended paths remain ignored.

Written by the indexing model from the issue text.