chore(POCP-1226): support 8-digit IINs in card event

[lukasz-k-bieszczad-cko]

Description

The PO.JS card event exposed a card's IIN capped at 6 digits. Civitatis needs 8 digits to call MercadoPago's GET /installments directly. This widens the SDK's IIN handling to 8 digits.

Solution

• Card.getIIN cap raised 6 → 8. Canonical IIN extractor, so the card field event and everything derived from the IIN now carries up to 8 digits. Scheme/length/format detection is prefix-based, so no behavioural change for existing 6-digit cards.
• getCardInformation no longer truncates its input to 6 digits before the iins/{iin} lookup - passes through up to 8. Minimum-length guard (6) unchanged.
• Dynamic Checkout IIN restriction (restrict_to_iins) matching changed from exact equality to prefix match, so an 8-digit card_iin still matches 6-digit allowlist entries (and vice versa). Guards against cards being wrongly blocked once the event emits 8 digits.

Checklist

• I bumped the version of the project using yarn bump-version
• I have checked the code for any potential issues
• I tested my changes in the browser

Jira Issue

POCP-1226

[Copilot]

Pull request overview

This PR updates the SDK’s card IIN handling to support up to 8-digit IINs, enabling more accurate issuer lookups (notably for MercadoPago installments) while preserving compatibility with existing 6-digit behavior.

Changes:

• Increase IIN extraction cap from 6 → 8 digits in Card.getIIN.
• Update ProcessOut.getCardInformation to use up to 8 digits for the iins/{iin} lookup (minimum length remains 6).
• Adjust Dynamic Checkout restrict_to_iins matching from exact equality to prefix-based matching.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
src/processout/processout.ts	Expands IIN lookup in getCardInformation from 6 to 8 digits.
src/processout/card.ts	Raises Card.getIIN maximum returned length from 6 to 8 digits.
src/dynamic-checkout/payment-methods/card.ts	Changes restrict_to_iins allowlist evaluation to use prefix matching.
package.json	Bumps package version to 1.9.8.

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[lukasz-k-bieszczad-cko]

Tests

ProcessOut.Card.getIIN("4242424242424242")
'42424242'

po.getCardInformation("42424242", console.log, console.error)
{
    "card_information": {
        "bank_name": "STRIPE PAYMENTS UK LIMITED",
        "brand": "visa classic",
        "category": "consumer",
        "co_scheme": null,
        "combo_card_types": null,
        "country": "GB",
        "scheme": "visa",
        "type": "credit"
    },
    "success": true
}