Worktree 0.18.1

• Every dependency moves to its newest release; behaviour is unchanged.
• Cargo requirements: rusqlite 0.37 to 0.40 (lock 0.37.0 to 0.40.2), sha2 0.10 to 0.11
  (0.10.9 to 0.11.1), toml 0.9 to 1.1 (0.9.12 to 1.1.8).
• Cargo lock: serde_json 1.0.151 to 1.0.154, thiserror 2.0.20 to 2.0.21, uuid 1.26.1 to
  1.28.0, and their transitive crates.
• rust-version 1.85 to 1.89, which uuid 1.28 and sha2 0.11.1 need.
• Workflows: actions/checkout v4 to v7 and arduino/setup-task v2 to v3 in the gate, now
  pinned by commit; dtolnay/rust-toolchain at the current stable head; upload-artifact
  v7.0.1 to v7.0.2; download-artifact v8.0.1 to v8.0.2; the shared source gate at its 0.1.18
  release.