Simplifications and clean ups to the runtime_service

[tomaka]

See individual commits.

This attempts at cleaning up the code of the service and making it easier to read and understand.

[mergify]

Automatically approving tomaka's pull requests. This auto-approval will be removed once more maintainers are active.

[github-actions]

twiggy diff report

Difference in .wasm size before and after this pull request.

---

 Delta Bytes │ Item
─────────────┼────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
      -12101 ┊ smoldot::network::service::ChainNetwork<TNow>::next_event::{{closure}}::hbd102ed669b6ae15
      +12101 ┊ smoldot::network::service::ChainNetwork<TNow>::next_event::{{closure}}::hffe05df3b4dba7cb
      -11853 ┊ <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll::h0e91ac0548663e0b
      +11853 ┊ <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll::hcfa24ecbc5cda2fb
      +11342 ┊ <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll::hab58f018371ee2ca
      -11342 ┊ <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll::hb330ba3a988c4797
      -10121 ┊ <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll::h716ea87a926542db
      +10121 ┊ <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll::ha61c0f1bf19ee8cf
       +9935 ┊ smoldot::libp2p::connection::established::substream::Substream<TNow,TRqUd,TNotifUd>::read_write2::hd58b0e56085829c8
       -9935 ┊ smoldot::libp2p::connection::established::substream::Substream<TNow,TRqUd,TNotifUd>::read_write2::heefa7401a5ca14b2
       -8937 ┊ smoldot_light_base::Client<TChain,TPlat>::add_chain::h9182a7df5a1f8064
       +8937 ┊ smoldot_light_base::Client<TChain,TPlat>::add_chain::hb6f8871050d47773
       -7811 ┊ <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll::h1b5f251e2271db9a
       +7769 ┊ <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll::h20c3fdbb4438cefe
       +6739 ┊ <&mut serde_json::de::Deserializer<R> as serde::de::Deserializer>::deserialize_map::h47215ba8aa4d15bb
       -6739 ┊ <&mut serde_json::de::Deserializer<R> as serde::de::Deserializer>::deserialize_map::hd3fbff4492efddb0
       +6150 ┊ <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll::h66217759a1c827a2
       -6150 ┊ <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll::hc08c77ba2819f277
       +5852 ┊ <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll::h44c1fc6e0e4c14af
       -5852 ┊ <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll::hf8a0d83e3b74eb3e
       -2658 ┊ ... and 16507 more.
       -4221 ┊ Σ [16527 Total Rows]

[melekes]

magic numbers?

[tomaka]

Yeah, I agree it's not great. These functions are only used in order to respond to some JSON-RPC methods, and so we have no choice but to use magic numbers anyway. The question is just where to put these magic numbers.

I think these functions should be moved to the json_rpc_service. I'll do that in a follow-up PR if you don't mind.