feat(provisioning): admin game-signup mode setting, invite link option, staff self-create

Follow-ups from live testing:

- Game-account creation is now an admin Settings control (disabled / website /
  hybrid / game) instead of a hidden on/off flag. The site offers creation for
  website+hybrid; help text notes the shard's SignupMode (Bridge.cfg) has the final
  say. game_account_signup setting widened to a 4-value enum + validated on save.
- Invites: the accept link is ALWAYS returned and shown with a Copy button, and a
  "Email the invitation" toggle lets an admin create a link-only invite (no email)
  or email it. Backend takes sendEmail (default true) and always returns acceptUrl.
- Staff can create a game account from their own /admin/characters page too
  (POST /admin/shard/account → the shared createGameAccount controller), so the
  form is reachable in both the player and admin portals.

Note: the admin Houses view (/admin/houses) already worked; the earlier failure
was a stale Vite HMR state for the new route (needs a hard refresh).

Client build clean; server routes load; swagger regenerated.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

server/src/router/v1/admin/invites.controller.js

@@ -22,10 +22,14 @@ function acceptUrl(token) {
   return `${baseUrl()}/invite/${token}`
 }
 
-// POST /admin/invites — create an invite and email it.
+// POST /admin/invites — create an invite. Optionally email it (sendEmail, default
+// true); the copyable accept link is ALWAYS returned so the admin can hand it over
+// directly. The token is single-use + expiring and the caller is the authenticated
+// admin who made it, so echoing the link back to them is safe.
 async function create(req, res) {
   const email = String(req.body.email || '').trim()
   const role = req.body.role
+  const sendEmail = req.body.sendEmail !== false // default true
   if (!email || !ROLES.includes(role)) {
     return res.status(400).json({ message: 'A valid email and role are required.' })
   }
@@ -33,24 +37,26 @@ async function create(req, res) {
     const { invite, token } = await invites.create({ email, role, invitedBy: req.user.id })
     const url = acceptUrl(token)
 
-    // Send the email; if mail isn't configured, hand the link back so the admin
-    // can share it manually. A send failure doesn't delete the invite — surface it.
+    // Send the email only if asked. A send failure doesn't delete the invite — the
+    // link is still returned so the admin can share it manually.
     let emailed = false
     let emailError = null
-    try {
-      const result = await mailer.sendInvite({ to: email, acceptUrl: url, role, invitedByName: req.user.username })
-      emailed = Boolean(result.sent)
-    } catch (err) {
-      emailError = err.message
-      log.warn('invite email failed (invite still created)', { id: invite.id, message: err.message })
+    if (sendEmail) {
+      try {
+        const result = await mailer.sendInvite({ to: email, acceptUrl: url, role, invitedByName: req.user.username })
+        emailed = Boolean(result.sent)
+        if (!result.sent && result.reason === 'NOT_CONFIGURED') emailError = 'email is not configured'
+      } catch (err) {
+        emailError = err.message
+        log.warn('invite email failed (invite still created)', { id: invite.id, message: err.message })
+      }
     }
 
     await activity.log({ req, userId: req.user.id, action: 'invite.create', detail: { email, role, emailed } })
     log.info('invite created', { id: invite.id, email, role, emailed, by: req.user.username })
 
-    // The accept link is returned only when email did not deliver, so the admin
-    // can copy it. When emailed, we don't echo the token.
-    return res.status(201).json({ invite, emailed, acceptUrl: emailed ? undefined : url, emailError })
+    // acceptUrl is always returned (copyable link); emailed says whether it also went out.
+    return res.status(201).json({ invite, emailed, acceptUrl: url, emailError })
   } catch (err) {
     log.error('create invite', err)
     return res.status(500).json({ message: 'Internal Server Error' })