horizon/effects-processor: add some error checking during ingestion

[tsachiherman]

This is a draft PR, used for education purposes only. Please DO NOT merge.

PR Checklist

PR Structure

• [ ] This PR has reasonably narrow scope (if not, break it down into smaller PRs).
• [ ] This PR avoids mixing refactoring changes with feature changes (split into two PRs otherwise).
• [ ] This PR's title starts with name of package that is most changed in the PR, ex. services/friendbot, or all or doc if the changes are broad or impact many packages.

Thoroughness

• [ ] This PR adds tests for the most critical parts of the new functionality or fixes.
• [ ] I've updated any docs (developer docs, .md files, etc... affected by this change). Take a look in the docs folder for a given service, like this one.

Release planning

• [ ] I've updated the relevant CHANGELOG (here for Horizon) if needed with deprecations, added features, breaking changes, and DB schema changes.
• [ ] I've decided if this PR requires a new major/minor version according to semver, or if it's mainly a patch change. The PR is targeted at the next release branch if it's not a patch change.

What

[TODO: Short statement about what is changing.]

Why

[TODO: Why this change is being made. Include any context required to understand the why.]

Known limitations

[TODO or N/A]

[tsachiherman]

Not sure why it says not to merge; more error checks seem like a good idea imo 👍 though I guess there is the rationale that we want to do "best effort processing" if we can continue without returning the error immediately.

Yes.. while it's true that more error checking is good, I don't have a way to test this change against the "expected success" path. So, I can't tell if any of the cases where we ignored the error was actually the desired behavior.