Remote session and client-controlled project identity authority

Chose credential-scoped, tenant-bound session resolution and disk Git identity over client-supplied project metadata, headers, or remotes because forged or stale values could cross project boundaries. Provisional validation must not mutate adopted state before complete proof; failed or malformed attempts expose only fixed gateway errors—never provider diagnostics, response prefixes, or statusText—and roll back re-attribution. Hosted mode never reads client workspace .lore.json.