Release Compass 0.1.8 for macOS, Linux, and Windows

[forhappy]

Summary

• bump the Compass workspace patch version from 0.1.7 to 0.1.8
• add native x86_64 and ARM64 Windows release artifacts alongside the existing macOS and Linux assets
• package compass.exe with licenses, notices, completions, and per-architecture SHA-256 files
• document the Windows archive installation path

Validation

• cargo test --workspace --lib --bins --locked
• cargo test -p compass-cli --test compass_product --locked (5 passed)
• sh scripts/test_release_scripts.sh (all six targets plus checksum rejection)
• cargo check --offline -p compass-cli --bin compass
• locked workspace metadata reports 0.1.8
• release workflow YAML parses with exactly six requested targets
• sh scripts/check_product_boundary.sh
• git diff --check
• graphify update .

The tag-triggered workflow will build, test, package, checksum, verify, and attest Intel/Apple Silicon macOS, x86_64/ARM64 Linux, and x86_64/ARM64 Windows artifacts.