fix(client/session): the declared GTK deps reach the lockfile

61bdf11e declared gtk4/libadwaita/relm4/async-channel on the session shell but
the corresponding Cargo.lock entries never rode along, and CI's `--locked`
clippy does not degrade to a re-resolve — it fails outright. One resolve,
no version changes.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Cargo.lock

@@ -3335,11 +3335,15 @@ name = "punktfunk-client-session"
 version = "0.21.0"
 dependencies = [
  "anyhow",
+ "async-channel",
  "glib-build-tools",
+ "gtk4",
+ "libadwaita",
  "pf-client-core",
  "pf-console-ui",
  "pf-presenter",
  "punktfunk-core",
+ "relm4",
  "serde_json",
  "tracing",
  "tracing-subscriber",