chore(*): add mathlib4 synchronization comments (#18944)
Regenerated from the [port status wiki page](https://github.com/leanprover-community/mathlib/wiki/mathlib4-port-status).
Relates to the following files:
* `algebra.continued_fractions.computation.basic`
* `algebra.continued_fractions.continuants_recurrence`
* `algebra.continued_fractions.convergents_equiv`
* `algebra.continued_fractions.terminated_stable`
* `algebra.continued_fractions.translations`
* `linear_algebra.lagrange`
* `measure_theory.function.ae_measurable_sequence`
* `measure_theory.measure.ae_disjoint`
* `measure_theory.measure.measure_space_def`
* `measure_theory.measure.null_measurable`
* `ring_theory.ideal.associated_prime`
