Improve subscription card display to properly handle current vs future subscription states
## Problem
The subscription card in the Customers Portal incorrectly displays future dated changes as if they are the current active subscription, creating significant usability issues due to how CustomersDot interacts with Zuora subscription versions.
### Root cause
When users create future-dated amendments (e.g., early renewal, plan upgrades), Zuora creates a new subscription version that becomes the "Active" subscription. CustomersDot references this latest/active subscription from Zuora, even though it hasn't taken effect yet. The actual current subscription still exists in Zuora's version history but is harder to access.
### Key issues
* **Visibility**: Users cannot see their actual current subscription details, products, pricing, or seat count - only the future state.
* **SM License Management**: Users can only download the new (future) license file, not their current active license.
* **Seat Management**: All seat additions apply only to the future subscription version, not the current one.
* **User Confusion**: Portal shows future products/seat counts as if they're currently active (e.g., shows "Ultimate" when user actually has "Premium").
### Example
A customer with Premium (5 users) who renews 15 days early and upgrades to Ultimate will immediately see "Ultimate" in the portal, can only download the Ultimate license, and cannot add seats to their current Premium subscription without support assistance.
## Proposal
Redesign the subscription card to display both current and future subscription states in a clear, user-friendly way that provides complete visibility without confusion.
### Requirements
* Customers can see their actual current subscription (what's effective today) separate from future changes.
* Customers can view current subscription details but subscription changes can only be made to the future version.
* Allow license downloads for both current and future subscription versions.
* Future subscription information is only shown when future-dated amendments exist.
* All user actions clearly indicate which subscription version they affect.
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