feat: invite member upsell for single-seat plans (#8801)

## Summary

- Show an upsell dialog when single-seat plan users try to invite
members, with a banner on the members panel directing them to upgrade.
- Misc fixes for member max seat display

## Changes

- **What**: `InviteMemberUpsellDialogContent.vue`,
`MembersPanelContent.vue`, `WorkspacePanelContent.vue`

## Screenshots

<img width="2730" height="1907" alt="image"
src="https://github.com/user-attachments/assets/e39a23be-8533-4ebb-a4ae-2797fc382bc2"
/>
<img width="2730" height="1907" alt="image"
src="https://github.com/user-attachments/assets/bec55867-1088-4d3a-b308-5d5cce64c8ae"
/>



┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-8801-feat-invite-member-upsell-for-single-seat-plans-3046d73d365081349b09fe1d4dc572e8)
by [Unito](https://www.unito.io)

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
Co-authored-by: GitHub Action <action@github.com>

src/locales/en/main.json

@@ -2176,7 +2176,7 @@
     "subscribeNow": "Subscribe Now",
     "subscribeToComfyCloud": "Subscribe to Comfy Cloud",
     "workspaceNotSubscribed": "This workspace is not on a subscription",
-    "subscriptionRequiredMessage": "A subscription is required for members to run workflows on Cloud",
+    "subscriptionRequiredMessage": "A subscription is required for members to run workflows on Cloud and invite members",
     "contactOwnerToSubscribe": "Contact the workspace owner to subscribe",
     "description": "Choose the best plan for you",
     "descriptionWorkspace": "Choose the best plan for your workspace",
@@ -2264,7 +2264,7 @@
       "placeholder": "Dashboard workspace settings"
     },
     "members": {
-      "membersCount": "{count}/50 Members",
+      "membersCount": "{count}/{maxSeats} Members",
       "pendingInvitesCount": "{count} pending invite | {count} pending invites",
       "tabs": {
         "active": "Active",
@@ -2280,6 +2280,9 @@
         "revokeInvite": "Revoke invite",
         "removeMember": "Remove member"
       },
+      "upsellBannerSubscribe": "Subscribe to the Creator plan or above to invite team members to this workspace.",
+      "upsellBannerUpgrade": "Upgrade to the Creator plan or above to invite additional team members.",
+      "viewPlans": "View plans",
       "noInvites": "No pending invites",
       "noMembers": "No members",
       "personalWorkspaceMessage": "You can't invite other members to your personal workspace right now. To add members to a workspace,",
@@ -2318,6 +2321,14 @@
       "message": "This member won't be able to join your workspace anymore. Their invite link will be invalidated.",
       "revoke": "Uninvite"
     },
+    "inviteUpsellDialog": {
+      "titleNotSubscribed": "A subscription is required to invite members",
+      "titleSingleSeat": "Your current plan supports a single seat",
+      "messageNotSubscribed": "To add team members to this workspace, you need a Creator plan or above. The Standard plan supports only a single seat (the owner).",
+      "messageSingleSeat": "The Standard plan includes one seat for the workspace owner. To invite additional members, upgrade to the Creator plan or above to unlock multiple seats.",
+      "viewPlans": "View Plans",
+      "upgradeToCreator": "Upgrade to Creator"
+    },
     "inviteMemberDialog": {
       "title": "Invite a person to this workspace",
       "message": "Create a shareable invite link to send to someone",
@@ -2964,8 +2975,9 @@
       "message": "You have unsaved changes. Do you want to discard them and switch workspaces?"
     },
     "inviteAccepted": "Invite Accepted",
-    "addedToWorkspace": "You have been added to {workspaceName}",
-    "inviteFailed": "Failed to Accept Invite"
+    "addedToWorkspace": "You have been added to:",
+    "inviteFailed": "Failed to Accept Invite",
+    "viewWorkspace": "View workspace"
   },
   "workspaceAuth": {
     "errors": {