fix(ramp): Correct ramp v2 order detail's crypto amount formatting

[imyugioh]

Description

Fixes excessive decimal places on the Order Details screen for ramp purchases. When buying crypto (e.g. ETH via Mercuryo), the cryptoAmount was displayed raw with up to 17 decimal digits (0.01588973776561068), breaking the layout.

Now the amount is formatted consistently with the home screen:

• Normal amounts are capped at 5 decimal places using formatWithThreshold (e.g. 0.01589 ETH)
• Very small amounts (< 0.0001) use subscript notation via formatSubscriptNotation (e.g. 0.0₅4567 BTC)
• Missing amounts show ...

Changelog

CHANGELOG entry: Fixed Order Details screen displaying excessive decimal places for crypto amounts after ramp purchases.

Related issues

Refs:

Manual testing steps

Feature: Order Details crypto amount formatting

  Scenario: Normal crypto amount is truncated to 5 decimal places
    Given the user has completed a buy order (e.g. ETH via Mercuryo)
    And the order cryptoAmount has many decimal places (e.g. 0.01588973776561068)

    When the Order Details screen is displayed
    Then the crypto amount is shown as "0.01589 ETH"
    And the layout is not broken by excessive decimals

  Scenario: Very small crypto amount uses subscript notation
    Given the user has completed a buy order with a very small amount (e.g. $5 of BTC)
    And the order cryptoAmount is less than 0.0001 (e.g. 0.00000456789)

    When the Order Details screen is displayed
    Then the crypto amount is shown with subscript notation (e.g. "0.0₅4567 BTC")

Screenshots/Recordings

Before

After

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Note

Low Risk
Low risk UI-only change that adjusts number formatting on the ramp Order Details screen and adds unit tests for edge cases (tiny, long-decimal, missing, and zero amounts).

Overview
Fixes ramp v2 Order Details to format cryptoAmount instead of rendering the raw number, preventing long decimals from breaking layout.

Amounts now prefer formatSubscriptNotation for very small values, otherwise use formatWithThreshold with a 5-decimal cap and current I18n.locale; missing amounts render as .... Adds tests covering long decimals, subscript formatting, missing values, and zero.

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