feat: write reserved rows with recording off, so post locks use wp_set_presence()

[josephfusco]

Any reserved _ client ID is now written with recording off, which is wider than the lock's own reasoning that it holds only what core's post meta did, and a lock window filtered below one second is the one input left untested.

Fixes #751

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[github-actions]

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 94.55%. Comparing base (1ac34ce) to head (67881d3).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##               main     #752   +/-   ##
=========================================
  Coverage     94.55%   94.55%           
  Complexity      268      268           
=========================================
  Files            29       29           
  Lines          3966     3966           
=========================================
  Hits           3750     3750           
  Misses          216      216           

Flag	Coverage Δ
multisite	94.55% <100.00%> (ø)
phpunit	73.82% <100.00%> (ø)

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[github-actions]

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