Release Compass 0.3.18

[forhappy]

Release

What changed

• Bump all Compass workspace metadata from 0.3.17 to 0.3.18, including all workspace Cargo.toml files, fuzz lockfile, vscode package, and qualification producer version.
• Move source-navigation release-note item into the 0.3.18 changelog section.
• Fix deprecation warning in release validation path (sha2::digest::generic_array::GenericArray::as_slice() -> as_ref()) in:
  • crates/compass-program/src/scip_stream.rs
  • crates/compass-core/src/program.rs

Validation run

• cargo check --workspace --all-targets --locked
• cargo fmt --all -- --check
• cargo clippy --workspace --lib --bins --locked -- -D warnings
• cargo test --workspace --lib --bins --locked
• cargo test -p compass-cli --test compass_product --locked
• sh scripts/check_product_boundary.sh
• sh scripts/test_release_scripts.sh
• ./scripts/qualify_code_graph_v1.sh --fixtures-only

Release notes (short): Restore standalone HTML source navigation for local-only graph commits with commit-safe permalinks.