Rewrite markers reducer in Typescript

[renchap]

The actions are not trivial because there are a few ways to invoke them. There is a standard way, a debounced way, and a "sync" way tries tried various methods, in case someone closes the tab before the request is received?

I think we could simplify this and have it all done in the same action, but I chose to not change too many things in this PR.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 82.70%. Comparing base (86500e3) to head (5356046).
Report is 415 commits behind head on main.

❗ Current head 5356046 differs from pull request most recent head 9b3162e. Consider uploading reports for the commit 9b3162e to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #27644      +/-   ##
==========================================
- Coverage   85.01%   82.70%   -2.32%     
==========================================
  Files        1059     1030      -29     
  Lines       28277    28152     -125     
  Branches     4538     4550      +12     
==========================================
- Hits        24040    23283     -757     
- Misses       3074     3786     +712     
+ Partials     1163     1083      -80     

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