feat(fleet): move bulk Remote OTA updates to Community tier (#1151)

Drops `requirePaid` from `POST /api/fleet/update-all` so Community admins
can dispatch bulk node updates. Per-node OTA was already Community-
reachable (admin-only); this completes the move so the full Remote OTA
surface ships at Community.

Frontend mirrors the backend: removes `canBulkUpdate` from
NodeUpdatesSheet so the "Update all (N)" affordance is purely data-
driven on `updatableRemoteCount > 0`.

Docs realigned to drop fence-spec and Skipper-only phrasing on the
Update all bulk action:
- features/licensing.mdx: Community line now lists Remote OTA (per-node
  and Update all); Skipper Fleet Actions parenthetical drops "bulk
  update all"
- features/remote-updates.mdx: Note rewritten to role-only requirement
- features/fleet-view.mdx: Update all (n) bullet drops the tier clause
- features/overview.mdx: Fleet View and Remote updates blurbs drop the
  Skipper/Admiral fences
- operations/upgrade.mdx: Note rephrased without naming tiers

Test coverage:
- fleet.test.ts: tier-gating spec flipped to assert Community access
- fleet-pilot-update.test.ts: bulk-OTA dispatch suite now spies tier
  to Community so it doubles as a regression guard

docs/features/overview.mdx

@@ -109,7 +109,7 @@ Connect containers across nodes by hostname over the Pilot tunnel so multi-node
 
 ### Fleet View
 
-Monitor your entire infrastructure from a single screen. The fleet dashboard shows all nodes with health metrics, container counts, and resource usage. Search, sort, filtering, stack drill-down, the Grid / Topology toggle, and critical-node detection are available on every tier; the bulk **Update All** action inside the Node Updates modal is Skipper or Admiral. [Learn more →](/features/fleet-view)
+Monitor your entire infrastructure from a single screen. The fleet dashboard shows all nodes with health metrics, container counts, and resource usage. Search, sort, filtering, stack drill-down, the Grid / Topology toggle, and critical-node detection are available on every tier. [Learn more →](/features/fleet-view)
 
 ### Fleet Federation
 
@@ -133,7 +133,7 @@ Create point-in-time snapshots of every compose file and environment file across
 
 ### Remote updates
 
-Check for outdated nodes and trigger over-the-air updates from the Fleet View. When the gateway is running a newer version than a remote node, a one-click update pulls the latest image and recreates the container automatically. Per-node updates and the Check Updates view are available on every tier; the bulk **Update All** action is Skipper or Admiral. [Learn more →](/features/remote-updates)
+Check for outdated nodes and trigger over-the-air updates from the Fleet View. When the gateway is running a newer version than a remote node, a one-click update pulls the latest image and recreates the container automatically. Both per-node updates and the bulk **Update all** action are available on every tier. [Learn more →](/features/remote-updates)
 
 ### Scheduled operations