Revert "Reduce usage of "any" (#448)"

[kraftp]

This reverts commit 8f1b5d4 as it included breaking API changes. It caused numerous failures on our demo applications and in our staging environment and cannot be released in its current state. The changes in that PR are good, but we need to introduce them gradually and carefully (likely in multiple smaller PRs) and verify they don't cause regressions.

[demetris-manikas]

I just submitted a fix for that

[kraftp]

I just submitted a fix for that

Unfortunately there were other issues, such as #463. More broadly, it's possible to write code like:

await ctx.setEvent<PresignedPost>("uploadkey", mkey);

Some apps have code like this (such as https://github.com/dbos-inc/dbos-demo-apps/tree/main/yky-social), and #448 broke them because those functions aren't generic any more. We shouldn't change public interface signatures in a non-backwards-compatible way. However, like I said, many of the changes in #448 were good (especially the internal changes) and we'd be happy to work with you to re-introduce them in smaller PRs. Thanks a lot for your contributions, we really appreciate them!