optionally exclude threads in direct messages (#29042)

* optionally exclude threads in direct messages

* add excludeDirect option in client4

* Skip flaky test

* refactor double negate

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Co-authored-by: Mattermost Build <build@mattermost.com>

server/channels/api4/user.go

@@ -3290,8 +3290,10 @@ func getThreadsForUser(c *Context, w http.ResponseWriter, r *http.Request) {
 	options.After = r.URL.Query().Get("after")
 	totalsOnlyStr := r.URL.Query().Get("totalsOnly")
 	threadsOnlyStr := r.URL.Query().Get("threadsOnly")
+	excludeDirectStr := r.URL.Query().Get("excludeDirect")
 	options.TotalsOnly, _ = strconv.ParseBool(totalsOnlyStr)
 	options.ThreadsOnly, _ = strconv.ParseBool(threadsOnlyStr)
+	options.ExcludeDirect, _ = strconv.ParseBool(excludeDirectStr)
 
 	// parameters are mutually exclusive
 	if options.Before != "" && options.After != "" {