feat(curator): archive + prune + list-archived (WS-4)

Catches the Curator surface up to Hermes v0.13's new write-side verbs
(`archive <skill>`, `prune`, `list-archived`, synchronous `run`). Adds
a new `CuratorService` actor in ScarfCore mirroring `KanbanService`'s
pattern (Sendable, pure I/O, `Task.detached(priority: .utility)` per
verb), tolerantly-decoded `HermesCuratorArchivedSkill` /
`CuratorPruneSummary` models, and `CuratorError` for inline-banner
surfacing.

Mac UX gains an "Archived" section between the leaderboards and the
last-report block (per-row Restore button), an "archivebox" button on
every active-skill leaderboard row to manually archive, a destructive
"Prune Archived…" confirm sheet enumerating each skill (template-
uninstall pattern — Cancel owns `.defaultAction`, Prune is on the red
`ScarfDestructiveButton`), and a synchronous-with-progress "Run Now"
on v0.13+ hosts (600s timeout, `ProgressView` while in-flight).
Failure path routes through a yellow inline error banner instead of a
modal alert. The legacy `CuratorRestoreSheet` stays accessible from
the overflow menu but only on pre-v0.13 hosts; on v0.13+ the per-row
Restore in the new Archived section replaces it.

All new surfaces gate on `HermesCapabilities.hasCuratorArchive` —
pre-v0.13 hosts see the v2.7.x layout unchanged. iOS picks up the new
`runNow(synchronous:)` signature with the v0.13 capability flag; the
read-only Archived section + WS-9 marker is left for the next stream.
14 new parser tests in `HermesCuratorParserTests` cover the JSON
happy path, the `{"archived": [...]}` envelope, the text fallback
(`--json` not supported), `"no archived skills"` sentinel folding,
prune-dry-run with both wrapper + bare-array shapes, and zero-skill
prune. All 369 ScarfCore tests pass; `xcodebuild` for the `scarf`
scheme succeeds.

Wire-shape unknowns (CLI flag presence on real v0.13) carry
`// TODO(WS-4-Q<N>)` markers in `CuratorService` and fall back
defensively when a flag isn't recognized. Implements WS-4 of Scarf
v2.8.0 (Hermes v0.13.0 catch-up). Plan:
scarf/docs/v2.8/WS-4-curator-archive-plan.md (on
coordination/v2.8.0-plans).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

scarf/Scarf iOS/Curator/CuratorView.swift

@@ -13,11 +13,24 @@ import ScarfDesign
 /// `HermesCapabilities.hasCurator` is true.
 struct CuratorView: View {
     @State private var viewModel: CuratorViewModel
+    @Environment(\.hermesCapabilities) private var capabilitiesStore
+
+    // TODO(WS-9): add a read-only "Archived" section mirroring the Mac
+    // surface (no per-row Restore/Prune mutations on iOS in this
+    // release). Gate on `capabilitiesStore?.capabilities.hasCuratorArchive`.
 
     init(context: ServerContext) {
         _viewModel = State(initialValue: CuratorViewModel(context: context))
     }
 
+    /// Whether the connected host runs curator synchronously. Threaded
+    /// into `runNow` so v0.13+ hosts block-with-spinner; pre-v0.13 fire
+    /// and forget. WS-9 will surface a richer iOS progress affordance
+    /// alongside the read-only Archived section.
+    private var archiveAvailable: Bool {
+        capabilitiesStore?.capabilities.hasCuratorArchive ?? false
+    }
+
     var body: some View {
         List {
             Section {
@@ -115,7 +128,7 @@ struct CuratorView: View {
     private var actionFooter: some View {
         HStack(spacing: 8) {
             Button {
-                Task { await viewModel.runNow() }
+                Task { await viewModel.runNow(synchronous: archiveAvailable, timeout: 600) }
             } label: {
                 Label("Run now", systemImage: "play.fill")
             }