projd-core 0.3.0

Core project scanning data model and analysis helpers for Projd.
Documentation
# projd-core

`projd-core` is the shared scanning model for Projd CLI and GUI. It detects
project markers, source languages, dependency manifests, tests, CI providers,
repository state, risks, project health, and per-language code line statistics.

The crate also provides project root discovery (`discover_roots`,
`DiscoverOptions`, `DiscoveredRoot`, `RootKind`) for directories that may
contain multiple independent projects with different VCS, build systems,
documentation sites, or datasets. Discovery terminates on detected root kinds
rather than directory depth.

Source control detection covers git, hg, svn, fossil, and bzr. Git, hg, and
svn populate branch / revision / last-commit / dirty fields by shelling out to
the corresponding CLI. Fossil and bzr currently report only marker presence;
the CLI-driven fields will be filled in a follow-up release. The `ProjectScan`
field is `vcs: VcsSummary` with `kind: VcsKind` (replaces the previous
`git: GitSummary` field as of 0.3.0).

This crate intentionally does not expose repository, homepage, or author metadata
in `Cargo.toml`, so published crates stay decoupled from local hosting details.