feat(core): Add ability to apply and see gift certificates on cart page

[jordanarldt]

What/Why?

• Update the cart page to allow applying gift certificates to a checkout.
• Update the cart page to correctly display gift certificates in the cart

Testing

Migration

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Latest commit: 03509bd

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Project	Deployment	Preview	Comments	Updated (UTC)
catalyst-b2b	Ready	Preview	Comment	Oct 27, 2025 10:04pm
catalyst-canary	Ready	Preview	Comment	Oct 27, 2025 10:04pm

1 Skipped Deployment

Project	Deployment	Preview	Comments	Updated (UTC)
catalyst	Ignored			Oct 27, 2025 10:04pm

[jorgemoya]

Looks good to me. Have some comments, but mostly 🍹 .