Module client_hub 

Minimalistic, type-safe ClientHub.

Design goals:

• Providers register an implementation once (local or remote).
• Consumers fetch by interface type (trait object): get::<dyn my::Api>().
• For plugin-like scenarios, multiple implementations of the same interface can coexist under different scopes (e.g. selected by GTS instance ID).

Implementation details:

• Key = type name. We use type_name::<T>(), which works for T = dyn Trait.
• Value = Arc<T> stored as Box<dyn Any + Send + Sync> (downcast on read).
• Sync hot path: get() is non-async; no hidden per-entry cells or lazy slots.

Notes:

• Re-registering overwrites the previous value atomically; existing Arcs held by consumers remain valid.
• For testing, just register a mock under the same trait type.

Structs

ClientHub

Type-safe registry of clients keyed by interface type.

ClientScope

A scope for resolving multiple implementations of the same interface type.

TypeKey

Stable type key for trait objects — uses fully-qualified type_name::<T>().

Enums

ClientHubError