feat(card): add cardDelegation transaction type

[Brunonascdev]

Explanation

This PR introduces a new TransactionType, cardDelegation, which is used to support setting the spending limit within the MetaMask Card mobile experience.

References

Checklist

• I've updated the test suite for new or updated code as appropriate
• I've updated documentation (JSDoc, Markdown, etc.) for new or updated code as appropriate
• I've communicated my changes to consumers by updating changelogs for packages I've changed
• I've introduced breaking changes in this PR and have prepared draft pull requests for clients and consumer packages to resolve them

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Note

Low Risk
Low risk, type-only change: extends TransactionType with a new enum value, which may require downstream consumers to handle the additional case in switch statements.

Overview
Adds a new TransactionType enum member, cardDelegation, to represent MetaMask Card spending-limit delegation transactions, including inline JSDoc describing its purpose.

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