feat(call): implement CallAdapter — ProtocolHandler for alknet/call (task: call/protocol/call-adapter)
Implement CallAdapter in protocol/adapter.rs: ProtocolHandler for ALPN
alknet/call with stream handling, per-request identity resolution (auth_token
overrides connection identity, falls back on failure), root context construction
(internal:false, deadline, capabilities+scoped_env from registration bundle),
env composition (CompositeOperationEnv with Layer 0 base + Layer 2 connection
overlay + optional Layer 1 session overlay), operationId leading slash stripped,
ResponseEnvelope→EventEnvelope conversion, PendingRequestMap sweeper, connection
drop fails all pending. SessionOverlaySource trait. 22 unit tests.
Refs: docs/architecture/crates/call/call-protocol.md
Implements: ADR-002, ADR-012, ADR-014, ADR-015, ADR-017, ADR-022, ADR-024
glm-5.2
2ff09a728c