Comb Synth demo hangs

[EvanKirshenbaum]

While working on refactoring codebase to pull out support code (#305), I noticed that the combinatorial synthesis demo was hanging in phase 5, after the reagent had been delivered:

I confirmed that this was also the case on the master branch, so it wasn't the recent changes that broke it and will probably take some effort to track down. This happens regardless of the number of drops going through in parallel (including just a single drop).

Migrated from internal repository. Originally created by @EvanKirshenbaum on Oct 05, 2023 at 10:11 AM PDT.

[EvanKirshenbaum]

After doing a lot of refactoring (#305) to get the code ready to release open-source, the demo now hangs before the first mix. Probably not worth spending time on before the release.

Migrated from internal repository. Originally created by @EvanKirshenbaum on Jan 22, 2024 at 12:39 PM PST.