Payments block: use 'purchase' copy for one-time payment plans

[agent-sandbox-automattic]

Description

Fixes MARMON-34. The Payments block was using 'subscription' copy even for one-time (non-recurring) payment plans. This PR conditionally renders 'purchase' language when the plan interval is one-time.

Changes

• extensions/shared/components/product-management-controls/utils.js: Changed the default plan title for one-time interval from 'Subscription' to 'One-time Payment', so new one-time plans created in the editor get a sensible default name.

• modules/memberships/class-jetpack-memberships.php: Added is_one_time_plan( $plan_id ) static helper that returns true when a plan's jetpack_memberships_interval post meta is 'one-time'.

• extensions/blocks/subscriber-login/subscriber-login.php: Updated render_block() to detect the current post's tier plan interval and use 'Manage purchase' as the default label (instead of 'Manage subscription') when the plan is one-time. Custom block attribute labels are still respected as before.

• changelog/marmon-34-one-time-purchase-copy: Added patch-level changelog entry.

Testing Instructions

1. Create a payment plan with interval One-Time Payment via any Payments/Recurring Payments block in the editor. Confirm the default plan name prefilled is "One-time Payment" (not "Subscription").
2. Gate a post behind a one-time payment tier. Add the Subscriber Login block with "Manage subscriptions link" enabled. Log in as a subscriber who purchased the one-time plan and confirm the link reads Manage purchase.
3. Repeat step 2 with a monthly/yearly recurring subscription tier. Confirm the link still reads Manage subscription.
4. Set a custom manageSubscriptionsLabel attribute on the Subscriber Login block. Confirm the custom label is used regardless of plan type.

Changelog

Significance: patch
Type: enhancement

Payments block: Use 'purchase' language instead of 'subscription' for one-time payment plans in the editor UI and the Subscriber Login block.

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Linear: MARMON-34

This PR was auto-generated by Agent Sandbox. Please review carefully before merging.

[github-actions]

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[github-actions]

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Code Coverage Summary

Coverage changed in 2 files.

File	Coverage	Δ%	Δ Uncovered
projects/plugins/jetpack/extensions/blocks/subscriber-login/subscriber-login.php	0/76 (0.00%)	0.00%	6 💔
projects/plugins/jetpack/modules/memberships/class-jetpack-memberships.php	89/411 (21.65%)	-0.11%	2 ❤️‍🩹

Full summary · PHP report · JS report

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