fix: thread manager bugs

[isekovanic]

CLA

• I have signed the Stream CLA (required).
• Code changes are tested

Description of the changes, What, Why and How?

This PR fixes 2 leftover issues in Threads v2:

• ThreadManager state being stale after logging out in an app
• Channel deletion not having a realtime effect on ThreadManager state

Changelog

[github-actions]

Size Change: +737 B (+0.16%)

Total Size: 457 kB

Filename	Size	Change
dist/browser.es.js	99.6 kB	+152 B (+0.15%)
dist/browser.full-bundle.min.js	56.5 kB	+108 B (+0.19%)
dist/browser.js	101 kB	+164 B (+0.16%)
dist/index.es.js	99.7 kB	+150 B (+0.15%)
dist/index.js	101 kB	+163 B (+0.16%)

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