Add API to get issue/pull comments and events (timeline) (#17403)

* Add API to get issue/pull comments and events (timeline)
Adds an API to get both comments and events in one endpoint with all required data.
Closes go-gitea/gitea#13250

* Fix swagger

* Don't show code comments (use review api instead)

* fmt

* Fix comment

* Time -> TrackedTime

* Use var directly

* Add logger

* Fix lint

* Fix test

* Add comments

* fmt

* [test] get issue directly by ID

* Update test

* Add description for changed refs

* Fix build issues + lint

* Fix build

* Use string enums

* Update swagger

* Support `page` and `limit` params

* fmt + swagger

* Use global slices

Co-authored-by: zeripath <art27@cantab.net>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>

routers/api/v1/api.go

@@ -842,6 +842,7 @@ func Routes(sessioner func(http.Handler) http.Handler) *web.Route {
 							m.Combo("/{id}", reqToken()).Patch(bind(api.EditIssueCommentOption{}), repo.EditIssueCommentDeprecated).
 								Delete(repo.DeleteIssueCommentDeprecated)
 						})
+						m.Get("/timeline", repo.ListIssueCommentsAndTimeline)
 						m.Group("/labels", func() {
 							m.Combo("").Get(repo.ListIssueLabels).
 								Post(reqToken(), bind(api.IssueLabelsOption{}), repo.AddIssueLabels).