feat: alkcall 0.9.0 adoption — bump to 0.7.0

The stub-sweep release changes no type alktty touches: the four
implemented stubs, the register_openable Pub-typed refusal (alktty's
op is Sub-typed), the register_imported Result return, and the removed
RelayError::PubTypedOpen are all surfaces alktty never exercises.

- alkcall requirement 0.8.1 -> 0.9.0; lockfile follows
- alktty 0.6.0 -> 0.7.0 (minor: raising the minimum alkcall requirement
  is ecosystem-coordination breaking on a 0.x crate)
- one test fix: `establisher_ok_on_valid_params` formatted a
  Result<Establishment, _> with {:?} — Establishment no longer derives
  Debug in alkcall 0.9.0; the assert now branches on Err and formats
  only the error

Verification: 113 default / 156 all-features tests, clippy
--all-targets -D warnings, fmt --check, cargo doc, fuzz corpus replay
(9 tests / 340 seeds), wasm32-unknown-unknown check + clippy,
publish --dry-run — all pass.

CHANGELOG.md

@@ -4,6 +4,40 @@ All notable changes to this crate are documented here. The format is
 based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/), and
 this crate adheres to [Semantic Versioning](https://semver.org/).
 
+## [0.7.0] - 2026-10-14
+
+The alkcall 0.9.0 adoption: a dependency bump only — no source change
+in alktty. alkcall 0.9.0 is the stub-sweep release (the marked-pub open
+contract, `channel/control`, `channel/resources/subscribe`, and
+`op/register` forward-through are real implementations). All of
+alkcall's semver-relevant changes (`ManagerError::InvalidAdopt`, the
+`RelayError::PubTypedOpen` removal, the `register_imported`
+`Result` return, `Establishment` losing `Debug`, the new
+`register_openable*` refusal of `Pub`-typed specs) touch surfacing
+alktty never uses — alktty's open op is `Sub`-typed and it only
+constructs `Establishment` (whose `new` is unchanged). The wire format,
+the direct-ALPN path, the `TtyBackend` trait, and alktty's public API
+surface are unchanged.
+
+### Changed
+
+- **BREAKING (ecosystem-coordination) — `alkcall` bumped to 0.9.0.**
+  alkcall 0.9.0 changed no type that alktty touches: the open-op
+  machinery alktty registers through (`ChannelCore`/
+  `register_openable_with_establisher`/`OpenEstablisher`/`OpenHandler`
+  /`Establishment`/`ChannelPlan`, `ChannelClient::open_channel`,
+  `ChannelOpenError::CallFailed`) is shape-identical to 0.8.1 — the
+  four stub implementations are net-new surfaces on ops alktty does
+  not exercise, the established-wrapper refusal of `Pub`-typed specs
+  does not apply to alktty's `Sub`-typed open op, and the removed
+  `RelayError::PubTypedOpen` was never referenced. alktty's public
+  signatures reference alkcall types, so downstream crates must now
+  unify on alkcall 0.9.0. Minor bump per the 0.x
+  ecosystem-coordination rule (raising the minimum requirement is
+  breaking — hence 0.7.0, not a patch release).
+- **`alkcall` requirement updated to `0.9.0`; lockfile bumped from
+  0.8.1 to 0.9.0.**
+
 ## [0.6.0] - 2026-09-28
 
 The fuzzing adoption: a cargo-fuzz workspace over the four wire-facing
@@ -405,6 +439,7 @@ alknet mono-repo.
   the client→backend pump is aborted at session end instead of
   lingering until the client disconnects.
 
+[0.7.0]: https://git.alk.dev/alkdev/alktty/releases/tag/v0.7.0
 [0.6.0]: https://git.alk.dev/alkdev/alktty/releases/tag/v0.6.0
 [0.5.0]: https://git.alk.dev/alkdev/alktty/releases/tag/v0.5.0
 [0.4.1]: https://git.alk.dev/alkdev/alktty/releases/tag/v0.4.1