* fix: drop Cirrus CI (going away June 1, 2026)
Signed-off-by: Henry Schreiner <henryfs@princeton.edu>
* Restore missing note
* Update CI services documentation for Cirrus CI
Removed official support for Cirrus CI due to end-of-life.
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Signed-off-by: Henry Schreiner <henryfs@princeton.edu>