Remove the assigned-user and label filters

Workflows now move every overdue card of their source stack. A new
migration drops filter_user_ids and filter_label_ids; workflows that
had a filter keep running unfiltered. The version goes to 35.1.0 so
the migration runs on update.

Removed along with the filters: the labels and participants endpoints
and their Deck lookups, the dead-filter warnings and markers, and
CardService::enrichCards() in the card read. enrichCards() only added
labels, assignees and comment counts, and ran a permission check
against Deck's frozen uid.

src/api.js

@@ -33,13 +33,3 @@ export async function fetchStacks(boardId) {
 	const { data } = await axios.get(ocsUrl(`/boards/${boardId}/stacks`))
 	return data.ocs.data
 }
-
-export async function fetchLabels(boardId) {
-	const { data } = await axios.get(ocsUrl(`/boards/${boardId}/labels`))
-	return data.ocs.data
-}
-
-export async function fetchParticipants(boardId) {
-	const { data } = await axios.get(ocsUrl(`/boards/${boardId}/participants`))
-	return data.ocs.data
-}