chore: bump to 0.8.1, changelog for the alkcall 0.10.1 adoption

- alkcall requirement 0.10.0 -> 0.10.1 (same-family version-only bump:
  the adoption-window ordering fix, private fix surface, no type alktty
  touches); lockfiles updated in both the root and fuzz workspaces
- AGENTS.md pin refreshed from the stale 0.9.0 note

Verification: cargo test 113 default / 137 all-features (unchanged from
the 0.8.0 baseline); fuzz corpus replay 9 green; clippy stable + wasm
(-D warnings); fmt; doc; wasm32-unknown-unknown check; publish dry run
(43 files)

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "alktty"
-version = "0.8.0"
+version = "0.8.1"
 edition = "2021"
 rust-version = "1.88"
 license = "MIT OR Apache-2.0"
@@ -29,7 +29,7 @@ default = []
 local = ["dep:portable-pty", "dep:tokio-util", "tokio/process", "tokio/rt-multi-thread"]
 
 [dependencies]
-alkcall = "0.10.0"
+alkcall = "0.10.1"
 # Minimal, wasm-clean tokio features. `local` adds `process` +
 # `rt-multi-thread` (non-wasm). Do NOT use `features = ["full"]` — it
 # pulls in `signal`/`fs`/`net` which break `wasm32-unknown-unknown`.