* feat(hitless): Introduce handlers for hitless upgrades
This commit includes all the work on hitless upgrades with the addition
of:
- Pubsub Pool
- Examples
- Refactor of push
- Refactor of pool (using atomics for most things)
- Introducing of hooks in pool
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Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
