adapter: synthesize and apply side effects (aka. controller commands) from catalog changes

[aljoscha]

First step towards #29279

With this we only wire up the new side-effects logic for
creating/dropping tables.

Motivation

Tips for reviewer

Checklist

• This PR has adequate test coverage / QA involvement has been duly considered. (trigger-ci for additional test/nightly runs)
• This PR has an associated up-to-date design doc, is a design doc (template), or is sufficiently small to not require a design.
• If this PR evolves an existing $T ⇔ Proto$T mapping (possibly in a backwards-incompatible way), then it is tagged with a T-proto label.
• If this PR will require changes to cloud orchestration or tests, there is a companion cloud PR to account for those changes that is tagged with the release-blocker label (example).
• If this PR includes major user-facing behavior changes, I have pinged the relevant PM to schedule a changelog post.

[def-]

Still in draft, but I triggered nightly: https://buildkite.com/materialize/nightly/builds/9650 and it shows an interesting panic:

platform-checks-mz_1-1              | thread 'coordinator' panicked at src/adapter/src/coord/ddl.rs:174:9: cannot apply ops that produce side effects when using catalog_transact_with_side_effects