Merge #1500: Overhaul stats: Improve torrent-repository package before adding events (part 2)

4d91738 refactor: [#1495] renamings in torrent-repository pkg (Jose Celano)
5b3142f refactor: [#1495] refactor Swarms::upsert_peer (Jose Celano)
5c2c1e0 feat: [#1495] add len and is_empty methods to Swarms type (Jose Celano)
31f1fbf refactgor: [#1495] make field private (Jose Celano)
6d50fa0 refactor: [#1495] remove panics from Swarms type (Jose Celano)
5413e59 refactor: [#1495] renamings to follow latest changes in torrent-repository pkg (Jose Celano)
6f5cb27 refactor: [#1495] remove test for SwarmHandle (Jose Celano)

Pull request description:

  Improve `torrent-repository` package before adding events.

  This is a continuation of [tracker/issues/1495](#1497).

  #### Refactoring `TorrentRepository`

  - [x] Return errors instead of panicking in `Swarms` type.
  - [x] Make field `swarms` private.
  - [x] Add `len` and `is_empty` methods.
  - [x] Refactor `upsert_peer`.
  - [x] Renamings to follow the latest changes in type names.

ACKs for top commit:
  josecelano:
    ACK 4d91738

Tree-SHA512: 4ee9be1c21a62148d0d4fa0a9263c54312239fc98e2540d7583689a50126883ba563b5c676a606196c5696b14a4452a14061159b3ac2c69dd02c493c7930ceaf

Author: josecelano

Cargo.lock

@@ -19,11 +19,11 @@ version.workspace = true
 aquatic_udp_protocol = "0"
 bittorrent-primitives = "0.1.0"
 crossbeam-skiplist = "0"
+thiserror = "2.0.12"
 tokio = { version = "1", features = ["macros", "net", "rt-multi-thread", "signal", "sync"] }
 torrust-tracker-clock = { version = "3.0.0-develop", path = "../clock" }
 torrust-tracker-configuration = { version = "3.0.0-develop", path = "../configuration" }
 torrust-tracker-primitives = { version = "3.0.0-develop", path = "../primitives" }
-tracing = "0"
 
 [dev-dependencies]
 async-std = { version = "1", features = ["attributes", "tokio1"] }

packages/torrent-repository/Cargo.toml

@@ -23,7 +23,7 @@ pub trait LockTrackedTorrent {
     fn lock_or_panic(&self) -> MutexGuard<'_, Swarm>;
 }
 
-impl LockTrackedTorrent for Arc<Mutex<Swarm>> {
+impl LockTrackedTorrent for SwarmHandle {
     fn lock_or_panic(&self) -> MutexGuard<'_, Swarm> {
         self.lock().expect("can't acquire lock for tracked torrent handle")
     }