Canonical project identity

SV2-IDN-01 adds ProjectIdentity.project_id to resolve_project and attributes(). The previous project, repo, cwd, worktree and remote fields remain readable. Paths and basenames describe local provenance. They grant no authority and are not global IDs.

canonical_remote reads no network service. The resolver observes the checkout’s Git origin configuration. HTTPS, SSH URLs with optional git user, and git@host:owner/repo forms resolve to host/owner/repo. Host case is normalized; GitHub owner and repository case is normalized too. Other forges retain owner and repository case. A trailing slash and .git suffix are removed. Linked worktrees use the same Git common directory as their primary checkout. Separate clones may use different local names.

Credential-bearing remotes and ambiguous forms resolve to unknown with an empty exported remote. Paths, query strings, fragments, ports, nested forge groups, usernames other than git, and hosts without a dot are unsupported. Diagnostics never include the rejected remote. Existing Git configuration is read without rewriting it.

For non Git projects, the registration authority supplies AGENTIHOOKS_PROJECT_ID=local:<id>. An ID starts with an alphanumeric character, then has at most 127 alphanumeric, dot, underscore or dash characters. Registration survives a path change when the authority supplies the same ID. Missing registration stays unknown; an unowned folder without registration still returns None. Registration cannot override an observed Git project. In a swarm, registration applies to the configured repository, not the incidental cwd.

Repository renames use a persisted explicit map provided by the caller:

{"schema_version":"2.0","aliases":{"github.com/first/renamed":"github.com/first/common"}}

Pass that document as resolve_project(cwd, env, aliases=document). The renamed remote keeps the historical canonical ID; the legacy remote still describes the observed remote. The resolver validates the entire map, rejects cycles and noncanonical keys, follows chains, and never edits the map. The map’s maintainer owns which repositories are explicitly equated; no rename is inferred and no alias grants access.

The identity and map schema is urn:swarm-v2:project, version 2.0. Its wider forge support is metadata only; transport contracts currently accept GitHub, local and unknown IDs. Other forge IDs must wait for an explicit transport contract update before admission.

project_identity_ambiguities_total on each identity is one for unknown, otherwise zero. The caller aggregates these per resolution with its own fixture or execution dimensions. No global counter or network telemetry is created by the resolver.

Rollback retains the five preceding fields and reads historical records without project_id. Reverting the change or omitting an alias map does not delete stored evidence, registered IDs, or alias documents. The recovery test replays a persisted map and projects the result onto those five fields to rehearse this compatibility path.