[1.0.2 -> main] SHiP: Fix hang on exit

[heifner]

This is a temporary fix until issue #842 can be worked. Some alternatives were attempted, but no simple fix could be found that didn't require more work toward #842 then desired for 1.0.x. See AntelopeIO/appbase#34

Test runs of a hacked up state_history_plugin with sleeps that caused it to hang on almost every CI/CD run.
Example failures: https://github.com/AntelopeIO/spring/actions/runs/11076070901
With this fix: https://github.com/AntelopeIO/spring/actions/runs/11124229769

Merges release/1.0 into main including #845

Resolves #822

[ericpassmore]

Note:start
category: Other
component: SHiP
summary: Fix hang on exit, draining references to SHiP found in io_service.
Note:end