bombay — a typed behavior runtime.
The behavior half is [behavior]'s pure algebra (depended on, never
copied). Bombay Communication supplies the sole mailbox implementation. A
behavior is driven sequentially while its environment supplies events and
interprets effects. Runtime construction remains centralized in
[System::spawn]. Consumers that may publish an endpoint only after
initialization and its effects succeed use [System::activate].
Panic strategy
Actor task panics are normalized as [TaskOutcome::Panicked], and terminal
retirement completes during unwinding. The runtime therefore requires
panic = "unwind"; abort-mode programs cannot preserve these public
lifecycle outcomes.