Feature request: hiding (instead of editing/deleting) existing comment

## Describe the Feature

Being able to hide comments matching a regex, as an alternative to `delete-comment-regex` (or `edit-comment-regex` added in #26).

## Expected Behavior

Hiding existing comments, for example by using a `hide-comment-regex`.

## Use Case

Sometimes keeping old comments might make sense for historical/compliance reasons.

## Describe Ideal Solution

Not sure, open for thoughts.

## Alternatives Considered

1. `delete-comment-regex`
2. `edit-comment-regex` (added in #26)

But they don't keep the history in an equally accessible way.

## Additional Context

...

Start by tracing the existing `delete-comment-regex` and `edit-comment-regex` behavior, then review the GitHub API support for hiding comments. Define the command interface and visibility semantics, including permissions and historical access; done means matching existing comments can be hidden without deleting or editing them.

Written by the indexing model from the issue text.