Enable Holesail tunnels by default; keep holesail as required dep

Holesail is on unless ENABLE_HOLESAIL=0/false/off. The holesail package remains a required dependency; docs and UI copy match the new default.

server/services/holesail-tunnels.js

@@ -4,7 +4,8 @@
  * peardock control plane: HyperDHT + protomux-rpc
  * Data plane tunnels: Holesail L4 TCP/UDP reverse proxy (hs:// keys)
  *
- * Gated by ENABLE_HOLESAIL=1. Package: holesail (AGPL-3.0).
+ * Enabled by default. Set ENABLE_HOLESAIL=0 to disable.
+ * Package: holesail (AGPL-3.0) — required dependency.
  *
  * @see https://github.com/holesail/holesail
  * @see docs/HOLESAIL.md
@@ -62,8 +63,14 @@ function loadHolesail() {
   }
 }
 
+/**
+ * Holesail tunnels are on by default.
+ * Opt out with ENABLE_HOLESAIL=0 / false / off / no.
+ */
 export function isHolesailEnabled() {
-  return process.env.ENABLE_HOLESAIL === '1' || process.env.ENABLE_HOLESAIL === 'true'
+  const v = String(process.env.ENABLE_HOLESAIL ?? '1').trim().toLowerCase()
+  if (v === '0' || v === 'false' || v === 'off' || v === 'no') return false
+  return true
 }
 
 export function isHolesailAvailable() {
@@ -219,7 +226,7 @@ export function getTunnel(id) {
  */
 export async function createTunnel(opts = {}) {
   if (!isHolesailEnabled()) {
-    const err = new Error('Holesail tunnels disabled. Set ENABLE_HOLESAIL=1 to enable.')
+    const err = new Error('Holesail tunnels disabled. Remove ENABLE_HOLESAIL=0 to re-enable (on by default).')
     err.code = 'FEATURE_DISABLED'
     throw err
   }

server/services/metrics.js

@@ -89,8 +89,10 @@ export function getMetricsSnapshot(extra = {}) {
     features: {
       swarm: process.env.ENABLE_SWARM === '1' || process.env.ENABLE_SWARM === 'true',
       plugins: process.env.ENABLE_PLUGINS === '1' || process.env.ENABLE_PLUGINS === 'true',
-      holesail:
-        process.env.ENABLE_HOLESAIL === '1' || process.env.ENABLE_HOLESAIL === 'true',
+      holesail: (() => {
+        const v = String(process.env.ENABLE_HOLESAIL ?? '1').trim().toLowerCase()
+        return !(v === '0' || v === 'false' || v === 'off' || v === 'no')
+      })(),
       peerAllowlist:
         process.env.PEARDOCK_PEER_ALLOWLIST === '1' ||
         process.env.PEARDOCK_PEER_ALLOWLIST === 'true',