Separating crates

[rampage644]

This splits single runtime crate into several, some ideas and invariants:

• Prefer flat crate and directory structure
• Single "fat" binary crate (handles all the wiring and connecting dependencies)
• Switched to Rust 2024 edition (seem to be default for new crates for cargo init)

Some intermediate results

• My single use case was "Update SQL query test in executor/tests/query.rs, run test" time improved 3x-4x (30s -> 8s). I also believe it could be even further improved.

Upcoming (follow up) PRs

• Refactor error handling project-wise
• Restore tests that weren't migrated (Only test_parallel_queries left out)
• Refactor Recording service

Open questions

• Crate for just traits (interfaces) such that actual implementation stays separate. This PR effort is still not great from incremental compilation perspective. Example, api-*-rest depend on ExecutorService now AND CoreExecutor (real type that implements the trait) and thus every change in CoreExecutor (not the interface!) triggers dependent crates recompilation.
• tbd

Related #719

[rampage644]

Rebased on recent main