build(fuzz): require tines-core 1 and check the fuzz crate in ci.sh

fuzz/Cargo.toml still required tines-core 0.3.0, so since the 1.0.0
version bump `cargo fuzz run node` failed version selection (B6). The
requirement is now "1" and the lock is regenerated.

scripts/ci.sh now runs rustfmt and clippy (all targets, -D warnings) on
the out-of-workspace fuzz crate on the pinned stable toolchain, so it
can't silently stop building again. fuzz/.gitignore ignores target,
artifacts and coverage.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

fuzz/.gitignore

@@ -0,0 +1,3 @@
+target
+artifacts
+coverage

fuzz/Cargo.lock

@@ -277,7 +277,7 @@ dependencies = [
 
 [[package]]
 name = "tines-core"
-version = "0.3.0"
+version = "1.0.0"
 dependencies = [
  "blake2",
  "heapless",

fuzz/Cargo.toml

@@ -10,7 +10,7 @@ edition = "2021"
 cargo-fuzz = true
 
 [dependencies]
-tines-core = { path = "../tines-core", version = "0.3.0", features = ["conformance"] }
+tines-core = { path = "../tines-core", version = "1", features = ["conformance"] }
 libfuzzer-sys = "0.4"
 heapless = "0.8"
 

scripts/ci.sh

@@ -19,3 +19,8 @@ cargo test --locked -p tines-core --no-default-features
 # no_std + conformance combination is actually exercised (not just by inspection).
 cargo test --locked -p tines-core --no-default-features --features conformance
 sh scripts/check-no-std.sh
+# The fuzz crate sits outside the workspace and only *runs* on nightly
+# (cargo-fuzz, see .github/workflows/fuzz.yml), but it must keep resolving and
+# compiling on the pinned stable toolchain, or the scheduled job rots unseen.
+cargo fmt --manifest-path fuzz/Cargo.toml -- --check
+cargo clippy --locked --manifest-path fuzz/Cargo.toml --all-targets -- -D warnings