make deallocs not suck since using arena

src/threads.zig

@@ -18,16 +18,13 @@ const QueueWrap = struct {
             .job_pool = job_pool,
         };
     }
-    fn deinit(self: *Self) void {
-        self.job_pool.deinit();
-        self.alloc.destroy(self.queue);
-    }
 };
 
 pub const ThreadManager = struct {
     threads: std.ArrayList(std.Thread),
     arena: std.heap.ArenaAllocator,
     queue: QueueWrap,
+    job_pool: util.JobPool,
 
     const Self = @This();
 
@@ -40,13 +37,13 @@ pub const ThreadManager = struct {
             .threads = std.ArrayList(std.Thread).init(arena_alloc),
             .arena = arena,
             .queue = try QueueWrap.init(arena_alloc, job_pool),
+            .job_pool = job_pool,
         };
         return thread_mgr;
     }
 
     pub fn deinit(self: *Self) void {
-        self.threads.deinit();
-        self.queue.deinit();
         self.arena.deinit();
+        self.job_pool.deinit();
     }
 };