feat(coderd): add lookup task by name in httpmw.TaskParam (#20647)

* Adds a `GetTaskByOwnerIDAndName` query
* Updates `httpmw.TaskParam` to fall back to task name if no task by
UUID found.
* Updates the `TaskByIdentifier` used in `cli/` to use direct lookup instead of searching.

coderd/database/queries/tasks.sql

@@ -41,6 +41,13 @@ SELECT * FROM tasks_with_status WHERE id = @id::uuid;
 -- name: GetTaskByWorkspaceID :one
 SELECT * FROM tasks_with_status WHERE workspace_id = @workspace_id::uuid;
 
+-- name: GetTaskByOwnerIDAndName :one
+SELECT * FROM tasks_with_status
+WHERE
+	owner_id = @owner_id::uuid
+	AND deleted_at IS NULL
+	AND LOWER(name) = LOWER(@name::text);
+
 -- name: ListTasks :many
 SELECT * FROM tasks_with_status tws
 WHERE tws.deleted_at IS NULL