docs: R-97 shipped; N.5 gains its four legs; ops results recorded

R-97 collapsed to its shipped one-liner in ROADMAP and closed in OPEN-ITEMS.

PROMPT-TEMPLATE N.5 now names FOUR coupled artifacts instead of two: the
capability map, ROADMAP, the owning architecture doc (ruled as S-1 in CONTEXT.md
but never reflected in the template CC actually reads, so it bound nobody), and
OPEN-ITEMS.md. Tasks must now report which register rows they opened, closed or
re-ranked.

Ops: R-90 swap done (interim; CX33 still blocked), R-95 mitigation armed but zero
snapshots taken so it moves to WATCHING rather than closed, R-91 gate still not
satisfied. CONTEXT.md datastore path corrected to /mnt/pbs-datastore.

documentation/backlog/OPEN-ITEMS.md

@@ -10,19 +10,19 @@ State: `BLOCKED` · `READY` · `WAITING-ON-OPERATOR` · `WATCHING`. Every row ha
 |---|---|---|---|---|---|
 | **R-88a** | ~~Failing backup re-quiesces every 5 min, no backoff~~ | **SHIPPED** (controller v0.176.0, 2026-07-27) | — | Live on both boxes; breaker 15m→4h, per-tier, never permanent | — |
 | **R-88b** | `/backup/due` cannot say *unknown* — "read errored" and "never backed up" are byte-identical, so nil still bypasses the window gate | **READY #1** | — | Agent wire change: give unknown its own representation; compat rule both ways + MinAgent floor | CC |
-| **R-95** | restic offsite credential **can delete** (`readonly=False`, `forget --prune` runs from the box); SFTP cannot express append-only | **READY #2** | — | Snapshot plan as the stopgap (row below), then split prune off-box or move to REST `--append-only` | CC |
+| **R-95** | restic offsite credential **can delete** (`readonly=False`, `forget --prune` runs from the box); SFTP cannot express append-only | **READY #2** | — | Root exposure still open. Mitigation now ARMED — split prune off-box or move to REST `--append-only` | CC |
 | **R-94** | Hub hands out host-install `1.19.0`; `1.20.0` is what carries R-82's backup default | **READY #3** | — | Bump `configs.go:28`, and stop hand-syncing a version constant across repos | CC |
 | **R-86** | Restore-tests are interval-scheduled, not backup-aligned | **READY #4** | R-90 (ep0 headroom) informs cadence | Trigger a tier ~24 h after **its own** newest archive | CC |
 | **R-87** | The restic tier is never restore-tested | **READY #5** | — | Design a controller-side test (no scratch-guest analogue transfers) | CC |
-| — | Enable Hetzner Storage Box **snapshots** on `storage-box-pool-1` — `snapshot_plan=null`, 0/10 used, server-side so SFTP cannot delete them | WAITING-ON-OPERATOR | operator ruling | One console/API call; immediate immutability for the restic tier | operator |
+| — | Storage Box **snapshots** on `storage-box-pool-1` — plan SET (daily 00:00, keep 7) but **0 taken yet** | WATCHING | first run tonight 00:00 | Confirm `size_snapshots > 0` tomorrow; until then the mitigation is armed, not proven | CC |
 | — | `PBS-storage-1` (u629193, box 611421) still `status=active`, 19.9 MB | WAITING-ON-OPERATOR | operator console | Delete the box | operator |
-| **R-90** | ep0: 3.8 GB, **no swap**, OOM'd 2026-07-27 killing PBS for ~15 min | **BLOCKED** | Hetzner CX33 availability | Rescale; or add a swapfile as an interim (needs no console) | operator |
+| **R-90** | ep0 RAM headroom — **4 GiB swap added 2026-07-27** (persistent, verified without reboot); 3.8 GB RAM unchanged | **BLOCKED** (interim done) | Hetzner CX33 availability | Rescale when available; swap now covers Sunday's first GC | operator |
 | **R-91** | Old 13 GB datastore copy at `/srv/pbs-felhom` on ep0's root disk | WATCHING | demo-felhom's first **post-migration** PBS backup | Delete once it lands; fix `CONTEXT.md:1018` same commit | CC |
 | — | First-ever **GC** on `felhom-offsite` (armed today 13:11 UTC, never run) | WATCHING | schedule | **Sun 2026-08-02 04:30 UTC** — confirm it completes | CC |
 | — | demo-felhom's next weekly PBS backup (newest is 2026-07-26) | WATCHING | schedule | ~2026-08-02; also releases R-91 | CC |
 | — | demo-felhom's next restore-test (84 h cadence, last 2026-07-27 06:38 UTC) | WATCHING | schedule | ~2026-07-30 18:38 UTC | CC |
+| **R-97** | ~~Whole-guest backup tier had no hub signal; quiesce blamed the apps~~ | **SHIPPED** (controller v0.177.0 + hub v0.78.0, 2026-07-27) | — | Operator-only events proven end-to-end; app suppression is cycle-keyed with a 180 s expiring grace | — |
 | **R-89** | Retention as a per-customer **commercial** policy on the hub | READY (increment 2) | — | Policy object + reconciler → ep0 prune job; keep box tokens write-only | CC |
-| **R-96** | Two standing rules agreed in chat, never committed | READY (XS) | — | Add both beside `CONTEXT.md` S-1/S-2 | CC |
 | **R-92** | Hub PBS-DR gauge is 0.1 GB-granular — small deltas unverifiable | READY (XS) | — | Widen precision when retention becomes customer-visible | CC |
 | **R-93** | `drill-r50` is both a blocked customer and the only drift fixture | READY (XS) | — | Retire it for a synthetic fixture, or unblock + silence per-customer | CC |
 
@@ -32,7 +32,9 @@ State: `BLOCKED` · `READY` · `WAITING-ON-OPERATOR` · `WATCHING`. Every row ha
    that an unknown still fires the safety valve, so a read failure can take **one** out-of-window
    quiesce. Bounded now, but it is the fourth appearance of this class and the only one still open.
 2. **R-95** — the largest *data* exposure: the tier holding the customer's documents and photos is the
-   one whose credential can delete, and the mitigation is a console click nobody has made.
+   one whose credential can delete. The snapshot mitigation is now **armed** (daily 00:00, keep 7),
+   but it has taken zero snapshots so far and it does not touch the root cause — the box can still
+   `forget --prune` its own repo.
 3. **R-94** — a one-line constant, but until it moves every hub-driven install gets the pre-R-82
    backup default. Cheapest high-consequence fix on the list.
 4. **R-86** — an operator ruling already exists; it only waits on knowing what load ep0 can take.