Add architecture specs for the alknet-call crate:
- call-protocol.md: CallAdapter, EventEnvelope wire format, bidirectional
stream model with ID-based correlation, PendingRequestMap, protocol
operations (call/subscribe/batch/schema), per-request identity resolution,
connection/stream lifecycle, error codes
- operation-registry.md: OperationSpec, async Handler type, OperationRegistry,
AccessControl with trusted call bypass, OperationEnv with context
propagation (parent_request_id, identity inheritance), service discovery,
irpc integration layering, naming convention (no leading slash in names)
- ADR-012: Call protocol uses bidirectional QUIC streams with EventEnvelope
framing and ID-based correlation. Protocol is stream-agnostic and symmetric.
Resolves OQ-07.
Key design decisions:
- Handler type is async (Fn returning Pin<Box<dyn Future>>)
- OperationEnv::invoke propagates parent context (identity, metadata,
parent_request_id)
- Identity resolution is per-request, not per-connection
- Operation names without leading slash (fs/readFile, not /fs/readFile)
- Batch is a client-side pattern, not a protocol primitive (OQ-14)
- Phase 1 uses service/op paths, node prefix added later (OQ-13)
Also: promote ADR-010 and ADR-011 from Proposed to Accepted, add OQ-13
and OQ-14 to open-questions.md.
