Bug fix view and packet counter check

Refactored how checks are performed.

Before a single checker thread would handle all checks, with a single instance of all checker states, this lead to false positives when checking several links at the same time, often checks would fail when checks went from checking one link, to checking data from the other.

Now a new checker thread, along with its own state management, is spawned every time a link ID is observed for the first time. Each thread has its own "channel" (FIFO) where data is dispatched based on link ID. The dispatching logic is minimal and manually implemented, as the most obvious choice (Hash map) would be hopelessly inefficient for this case.