feat: Windows port — cross-platform path normalisation and CI matrix

[Hessesian]

Summary

Implements all critical and high-priority items from #127.

Changes

New: src/path_util.rs

Cross-platform path helpers:

• to_forward_slash(path) — converts Path to forward-slash string for globset (no-op on Unix)
• strip_unc_prefix(path) — strips \\?\ UNC prefix from canonicalize() result (no-op on Unix)
• file_stem_from_uri(uri) — URL-based file stem with fallback for driveless URIs

src/rg.rs — split_rg_fields

Adds Windows-aware split_rg_fields() that detects C:\ drive-letter prefix and skips that colon before splitting, so parse_rg_line and parse_rg_line_with_content_rooted work correctly on Windows.

src/indexer/discover.rs — globset forward-slash

Wires to_forward_slash into the 3 direct gs.is_match() calls in walkdir_find that bypassed the IgnoreMatcher::matches() wrapper.

Call sites — strip_unc_prefix + URL fix

• src/main.rs, src/indexer/apply.rs, src/indexer/cache.rs: wrap canonicalize() with strip_unc_prefix()
• src/indexer/apply.rs: remove bad format!(\"file://{}\", source_path) URI construction

CI / Release

• .github/workflows/ci.yml: add windows-latest to test matrix with choco install ripgrep fd
• .github/workflows/release.yml: add x86_64-pc-windows-msvc and aarch64-pc-windows-msvc release targets

Reference

Mechanical fixes modelled on qdsfdhvh/kotlin-lsp Windows branch.

Closes #127

[Copilot]

Pull request overview

Implements the Windows port tracked in #127 by centralizing path normalization, fixing rg output parsing for drive-letter paths, adding Windows to CI/release matrices, and tightening URL construction in tests.

Changes:

• New src/path_util.rs with to_forward_slash, strip_unc_prefix, and file_stem_from_uri, wired into globset matching (rg.rs, discover.rs), canonicalization (main.rs, apply.rs, cache.rs), and qualified-key generation (apply.rs).
• New split_rg_fields in src/rg.rs that skips a leading X: drive colon so parse_rg_line and parse_rg_line_with_content_rooted work on Windows; tests updated with #[cfg(windows)] variants.
• CI matrix extended with windows-latest (choco install ripgrep/fd) and release matrix extended with x86_64-pc-windows-msvc and aarch64-pc-windows-msvc (zip packaging); LSP smoke tests now canonicalize roots and build URIs via Url::from_file_path.

Reviewed changes

Copilot reviewed 19 out of 19 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/path_util.rs / src/path_util_tests.rs	New cross-platform path helpers + tests
src/rg.rs	Drive-letter-aware split_rg_fields; globset paths normalized via to_forward_slash
src/rg_tests.rs	Platform-specific rg parse inputs and backslash-normalized assertions
src/indexer/discover.rs	Direct GlobSet::is_match calls wrapped with to_forward_slash
src/indexer/apply.rs	Uses file_stem_from_uri + strip_unc_prefix; drops bad file:// URI concat and the corresponding starts_with check
src/indexer/cache.rs	workspace_cache_path strips UNC prefix; save_cache uses file_stem_from_uri
src/main.rs	Registers path_util module; --index-only root stripped of UNC prefix
src/indexer.rs / src/indexer_tests.rs / src/sidecar.rs	#[allow(dead_code)]/unused_imports to satisfy -D warnings on Windows
src/workspace/config_tests.rs	Normalize slashes for cross-platform comparison
src/inlay_hints_tests.rs / src/indexer/infer/it_this_tests.rs / src/features/references_tests.rs	Minor clippy/dead-binding cleanups
tests/lsp_smoke.rs	Canonicalize roots, strip UNC, use Url::from_file_path for URIs
.github/workflows/ci.yml	Tri-OS matrix with platform-specific tool install and -D warnings
.github/workflows/release.yml	Windows build targets with .zip packaging

[Copilot]

Pull request overview

Copilot reviewed 22 out of 22 changed files in this pull request and generated 3 comments.

Comments suppressed due to low confidence (1)

src/indexer/apply.rs:42

• The previous classify_source_set check accepted either a substring match against the raw source path or a file://<path> prefix match. After normalising source_path through to_forward_slash, only the substring check remains, and on Windows a configured source path containing backslashes (e.g. from workspace.json after <WORKSPACE> substitution on a Windows host, or a user-provided Windows path) will be converted to forward slashes here while the uri string already uses forward slashes encoded by Url::from_file_path (which also percent-encodes characters like spaces). For Unix this is a pure no-op so behaviour is preserved, but on Windows a source path containing a space or other percent-encodable character will silently no longer match — please verify with a Windows path containing a space, and consider parsing uri via Url::to_file_path() and comparing canonical PathBufs instead of doing a string contains.

fn classify_source_set(uri: &str, source_paths: &[String]) -> SourceSet {
    for source_path in source_paths {
        let normalized = to_forward_slash(std::path::Path::new(source_path));
        if uri.contains(&normalized) {
            return SourceSet::Library;
        }
    }
    if uri.contains("/src/test/")