Feature: Add support for pausing/resuming subscriptions

[jonwaldstein]

Description

This Epic adds support for pausing & resuming subscriptions to the gateway api. It also updates the donor dashboard to support pausing for Stripe gateways when applicable.

Includes the following pull requests:

• Feature: Add support for pausing/resuming subscriptions #7548
• Feature: add subscription pause UI for eligible payments #7549
• Feature: refine subscription management UI/UX #7557

Affects

• The Donor Dashboard

This PR will become a dependency of the following:

• https://github.com/impress-org/give-recurring/pull/1210
• https://github.com/impress-org/give-stripe/pull/506

Visuals

Testing Instructions

• Install Recurring: https://github.com/impress-org/give-recurring/actions/runs/11041121543
• Install Give Stripe Add-on: https://github.com/impress-org/give-stripe/actions/runs/11041142676
• Create a recurring donation with Stripe
• Access the donor dashboard and interact with the pause UI

Regression tests

• Donor Dashboard cancel subscription

Pre-review Checklist

• Acceptance criteria satisfied and marked in related issue
• Relevant @unreleased tags included in DocBlocks
• Includes unit tests
• Reviewed by the designer (if follows a design)
• Self Review of code and UX completed