Fix missing Note access checks in by moving Note#search to updated NoteFinder
Split from !2024 to partially solve https://gitlab.com/gitlab-org/gitlab-ce/issues/23867
## Which fixes are in this MR?
⚠️ - Potentially untested
💣 - No test coverage
🚥 - Test coverage of some sort exists (a test failed when error raised)
🚦 - Test coverage of return value (a test failed when nil used)
✅ - Permissions check tested
### Note lookup without access check
- [x] ✅ app/finders/notes_finder.rb:13 :download_code check
- [x] ✅ app/finders/notes_finder.rb:19 `SnippetsFinder`
- [x] ✅ app/models/note.rb:121 [`Issue#visible_to_user`]
- [x] ✅ lib/gitlab/project_search_results.rb:113
- This is the only use of `app/models/note.rb:121` above, but importantly has no access checks at all. This means it leaks MR comments and snippets when those features are `team-only` in addition to the issue comments which would be fixed by `app/models/note.rb:121`.
- It is only called from SearchController where `can?(current_user, :download_code, @project)` is checked, so commit comments are not leaked.
### Previous discussions
- [x] https://dev.gitlab.org/gitlab/gitlabhq/merge_requests/2024/diffs#b915c5267a63628b0bafd23d37792ae73ceae272_13_13 `: download_code` check on commit
- [x] https://dev.gitlab.org/gitlab/gitlabhq/merge_requests/2024/diffs#b915c5267a63628b0bafd23d37792ae73ceae272_19_19 `SnippetsFinder` should be used
- `SnippetsFinder` should check if the snippets feature is enabled -> https://gitlab.com/gitlab-org/gitlab-ce/issues/25223
### Acceptance criteria met?
- [x] Tests added for new code
- [x] TODO comments removed
- [x] Squashed and removed skipped tests
- [x] Changelog entry
- [ ] State Gitlab versions affected and issue severity in description
- [ ] Create technical debt issue for NotesFinder.
- Either split into `NotesFinder::ForTarget` and `NotesFinder::Search` or consider object per notable type such as `NotesFinder::OnIssue`. For the first option could create `NotesFinder::Base` which is either inherited from or which can be included in the other two.
- Avoid case statement anti-pattern in this finder with use of `NotesFinder::OnCommit` etc. Consider something on the finder for this? `Model.finder(user, project)`
- Move `inc_author` to the controller, and implement `related_notes` to replace `non_diff_notes`/`mr_and_commit_notes`
See merge request !2035
Replace issue access checks with use of IssuableFinder
Split from !2024 to partially solve https://gitlab.com/gitlab-org/gitlab-ce/issues/23867
## Which fixes are in this MR?
⚠️ - Potentially untested
💣 - No test coverage
🚥 - Test coverage of some sort exists (a test failed when error raised)
🚦 - Test coverage of return value (a test failed when nil used)
✅ - Permissions check tested
### Issue lookup with access check
Using `visible_to_user` likely makes these security issues too. See [Code smells](#code-smells).
- [x] 🚦 app/finders/notes_finder.rb:15 [`visible_to_user`]
- [x] 🚥 app/views/layouts/nav/_project.html.haml:73 [`visible_to_user`] [`.count`]
- [x] ✅ app/services/merge_requests/build_service.rb:84 [`issue.try(:confidential?)`]
- [x] ✅ lib/api/issues.rb:112 [`visible_to_user`]
- CHANGELOG: Prevented API returning issues set to 'Only team members' to everyone
- [x] ✅ lib/api/helpers.rb:126 [`can?(current_user, :read_issue, issue)`] Maybe here too?
- [x] ✅ lib/gitlab/search_results.rb:53 [`visible_to_user`]
### Previous discussions
- [ ] https://dev.gitlab.org/gitlab/gitlabhq/merge_requests/2024/diffs#b2ff264eddf9819d7693c14ae213d941494fe2b3_128_126
- [ ] https://dev.gitlab.org/gitlab/gitlabhq/merge_requests/2024/diffs#7b6375270d22f880bdcb085e47b519b426a5c6c7_87_87
See merge request !2031
