Stack timeouts: "Don't stack" stacks

[Nerixyz]

Checklist

• I'm reporting a problem with Chatterino
• I've verified that I'm running the most recent nightly build or stable release
• I've looked for my problem on the wiki
• I've searched the issues and pull requests for similar looking reports

Describe your issue

Setting the Stack timeouts setting to Don't stack will still cause timeouts to stack in channels where the user isn't mod. In channels where the user is a mod, only the PubSub messages don't stack and the IRC messages are swallowed.

(mod):
nerixyz timed out twitchdev for 10m.
nerixyz timed out twitchdev for 10m.
nerixyz timed out twitchdev for 10m.
twitchdev has been timed out for 10m.

(no mod):
twitchdev has been timed out for 10m. (4 times)

We don't have tests for PubSub, but at least for IRC (#5824 (comment)).

Screenshots

No response

OS and Chatterino Version

Chatterino Nightly 7.5.2-beta.1 (commit 553d331) built on 2025-01-04 with Qt 6.8.1, MSVC 194134120, Crashpad Running on Windows 10 Version 22H2, kernel: 10.0.19045