docs(architecture): remove removed-thing remnants from spec docs

Spec docs should describe WHAT IS, not WHAT WAS. ADRs and OQ files are
historical records by design and are left alone; the ADR-index Status
column records ADR status (stable fact). What changed in the specs:

- API code blocks no longer list removed methods. ChannelClient::connect_quic
  (channel-client.md) and CallClient::connect (client-and-adapters.md) are
  gone from the impl blocks; surrounding prose describes the current
  from_connection / spawn_dispatch primary + AlknetClient dial shape.
- Amendment (ADR-093): stream_types field is removed blockquotes dropped
  from channel-client.md and channel-operations.md (the code already
  reflects the current state).
- Historical is-removed / reversed-by / amended-by prose rewritten to
  current state across channels crate, call crate, hub, tls, core,
  endpoint, client READMEs, and the top-level README/overview.
- Dropped the EndpointError — removed subsection from endpoint/README.md
  (the type doesn't exist anymore, so it shouldn't have a subsection).
- Replaced stale connect() references in flow descriptions with the dial
  (in AlknetClient) since connect() is no longer a method.
- Removed strikethrough ADR-028 / from_jsonschema-clause rows from
  client-and-adapters.md and operation-registry.md ADR tables.
- Rewrote the ADR-066 update blockquote in operation-registry.md to
  describe FromJsonSchema's current shape.

19 files modified, net -116 lines. No ADRs or OQ files touched.

docs/architecture/crates/core/README.md

@@ -10,19 +10,16 @@ dispatch. Every handler crate depends on `alknet-core` for
 `ProtocolHandler`, `Connection`, `AuthContext`, `IdentityProvider`, and
 config types. The endpoint (`AlknetEndpoint`, `HandlerRegistry`) lives
 in [`alknet-endpoint`](../endpoint/README.md) (ADR-083 Amendment
-2026-07-15; `EndpointError` is removed — both variants were vestigial);
-core does not carry the accept-loop runner or its transport deps
-(quinn, iroh, rcgen, rustls-acme). `Connection::from_quinn` /
-`from_iroh` are in core's `types.rs` as shared constructors (gated on
-core's `quinn` / `iroh` features).
+2026-07-15); core does not carry the accept-loop runner or its
+transport deps (quinn, iroh, rcgen, rustls-acme).
+`Connection::from_quinn` / `from_iroh` are in core's `types.rs` as
+shared constructors (gated on core's `quinn` / `iroh` features).
 
 `ConnectionCredentials` and `RemoteIdentity` live in `alknet-core` (per
 ADR-091) — the transport-level credential bundle consumed by the dial
 (`alknet-client`) and by server-side transport construction. There is no
-call-protocol credential bundle: `CallCredentials` is removed (ADR-091
-Am. 2026-07-17 — its `auth_token` field had no reader; `auth_token` is
-a per-request payload field on `call.requested`, not a transport
-credential).
+call-protocol credential bundle; `auth_token` is a per-request payload
+field on `call.requested`, not a transport credential.
 
 ## Documents
 

docs/architecture/crates/core/core-types.md

@@ -374,7 +374,7 @@ registration bundle.
 |----------|-----|---------|
 | ProtocolHandler receives Connection, not BiStream | [ADR-007](../../decisions/007-bistream-type-definition.md) | Handlers that need multiple streams (SSH, call) have direct access to the Connection |
 | BiStream is a trait | [ADR-007](../../decisions/007-bistream-type-definition.md) | WASM door preserved, test mocks possible |
-| `Connection::from_stream` — generic single-stream connections | [ADR-065](../../decisions/065-connection-from-stream-generic-single-stream.md) | `from_stream`/`from_bidi` accept any `AsyncRead + AsyncWrite`; yield-once `accept_bi` contract; unblocks TCP+TLS, SSH channels, WebTransport, wasm; QUIC variants feature-gated, `Stream` variant always available; `MockConnection`/`ConnectionKind::Mock` removed (tests use `from_stream` with `sink`/`empty`) |
+| `Connection::from_stream` — generic single-stream connections | [ADR-065](../../decisions/065-connection-from-stream-generic-single-stream.md) | `from_stream`/`from_bidi` accept any `AsyncRead + AsyncWrite`; yield-once `accept_bi` contract; unblocks TCP+TLS, SSH channels, WebTransport, wasm; QUIC variants feature-gated, `Stream` variant always available; tests use `from_stream` with `sink`/`empty` |
 | `BidiStreamSource` — open `Connection` for extension | [ADR-070](../../decisions/070-bidistreamsource-trait.md) | `Connection` holds `Box<dyn BidiStreamSource>`; QUIC/iroh/stream wrap crate-private impls; `from_source` is the public constructor for downstream crates that implement the trait (channels, future transports); `from_quinn`/`from_iroh`/`from_stream`/`from_bidi` preserved; `close(code, reason)` kept on the trait (non-QUIC impls ignore the args — fixes the ADR-065 leftover clippy warning under `--no-default-features`) |
 | HandlerError is non-fatal | [ADR-010](../../decisions/010-alpn-router-and-endpoint.md) | Handler errors close the connection, not the endpoint |
 | SendStream/RecvStream wrap quinn + iroh + generic streams | [ADR-010](../../decisions/010-alpn-router-and-endpoint.md), [ADR-065](../../decisions/065-connection-from-stream-generic-single-stream.md) | Internal enum dispatch for QUIC sources and the generic `Stream` variant |

docs/architecture/crates/core/endpoint.md

@@ -7,8 +7,7 @@ last_updated: 2026-07-17
 
 > **This document is deprecated.** The `AlknetEndpoint` and
 > `HandlerRegistry` types live in a separate crate, `alknet-endpoint`
-> (ADR-083 Amendment 2026-07-15). `EndpointError` is removed (both
-> variants were vestigial). The canonical spec is
+> (ADR-083 Amendment 2026-07-15). The canonical spec is
 > [`crates/endpoint/README.md`](../endpoint/README.md).
 >
 > The shared types the endpoint imports (`ProtocolHandler`,