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/licensing.mdx

@@ -29,7 +29,7 @@ For larger deployments, an **Enterprise** tier is available with custom pricing,
 - Real-time container stats, global logs, the interactive network topology graph, and stack labels
 - Git sources for compose stacks
 - Multi-node management in both Proxy and Pilot Agent modes
-- Manual fleet snapshots (create, browse, restore, delete) and per-node Sencho updates
+- Manual fleet snapshots (create, browse, restore, delete) and Remote OTA node updates (per-node and **Update all**)
 - Custom S3-compatible backup target (bring your own AWS S3, Cloudflare R2, MinIO, Backblaze B2, or Wasabi bucket)
 - Vulnerability scanning: install, update, and uninstall Trivy, on-demand scans for vulnerabilities, secrets, and misconfigurations, plus scan comparison
 - CVE suppressions
@@ -49,8 +49,7 @@ For larger deployments, an **Enterprise** tier is available with custom pricing,
 - Scan policies with `block_on_deploy` deploy enforcement, SBOM (SPDX, CycloneDX), and SARIF export
 - Auto-update of the managed Trivy binary
 - Bulk actions on a label (deploy, stop, or restart every stack tagged with it)
-- Remote OTA node updates from the control instance
-- Fleet Actions (bulk update all, bulk restart Sencho)
+- Fleet Actions (bulk restart Sencho)
 - Blueprints and Fleet Secrets
 - Preset SSO for Google, GitHub, and Okta
 - Viewer accounts (1 admin plus 3 viewers)