Air-gapped sites

A box on an air-gapped site (license kind AirGapped) never talks to the server. The same steps run as files carried by USB or QR. Status reports fill the latest status and the graphs; usage reports become one row per period; the box is never shown gray for "no report".

Method · Route	Who	Effect · audit event
POST `/api/org/{slug}/roost/airgap/challenge`	Owner	`{ serial, productCert }` → the challenge file `{ typ: "roost-airgap-challenge", v: 1, serial, org, nonce, expiresAt, payloadToSign }`. Same rules and errors as `/bind/challenge`.
POST `/api/org/{slug}/roost/airgap/import`	Owner / Roost Admin (a bind entry needs the Owner seal `roost.bind`, subject `RoostBindSubject(slug, serial, nonce)`)	`{ file, stepUpAssertion? }` where `file` is the JSON text the box wrote: `{ typ: "roost-airgap", v: 1, serial, entries[] }`. Returns per-entry results and the file's SHA-256. `roost.airgap.imported`
GET `/api/org/{slug}/roost/airgap/export?serial=`	Owner / Roost Admin	The file to carry to the box: `{ serial, file, fileHash, keyFingerprint, content }`. `file` = `base64url(payload).base64url(signature)` with the Roost identity key (verify with `GET /api/roost/identity-public-key`); `content` = `{ typ: "roost-airgap-out", v: 1, serial, org, issuedAt, lifecycleState, boundAt, enrollment, timePolicy, rollouts[], expectedMeasurements }`. `503 ROOST_IDENTITY_KEY_MISSING`. `roost.airgap.exported`
GET `/api/org/{slug}/roost/usage?days=30`	Owner / Roost Admin	`{ from, to, boxes[], days[{ date, signs }], windowTotal, reports[] }` — daily seal counts are differences of each box's monotonic sign counter; `reports` are the usage reports imported from files.

Import file entries

`kind`	Fields	Rule
`bind`	`nonce`, `boxSignature` (ECDSA P-256 `r‖s`, base64url, over the challenge payload)	At most one, processed first. The whole file is refused when the seal or the signature fails.
`status`	`payload`, `signature` — the `/api/roost/report` envelope, payload `roost-status` v1	Applied in time order. Older than the last accepted report → `REPORT_REPLAYED`; more than 5 minutes in the future → `REPORT_CLOCK_SKEW`. Past times are accepted (that is the point).
`usage`	`payload`, `signature` — payload `{ typ: "roost-usage", v: 1, serial, at, periodStart, periodEnd, counterStart, counterEnd, servers }` (times in Unix seconds)	One row per box and `periodStart`; a repeated report answers `duplicate: true`. `signs = counterEnd − counterStart`.