fix: show correct decimal places when managing price alerts

[juanmigdr]

Description

formatPriceWithSubscriptNotation was capping decimal places at 4 for values under 1, which meant two similar thresholds like $0.00181069 and $0.00182069 would both display as $0.0018. Added a maximumFractionDigits override so the manage alerts list can pass 15 and preserve the stored precision.

Changelog

CHANGELOG entry: show correct decimal places when managing price alerts

Related issues

Fixes: https://consensyssoftware.atlassian.net/browse/ASSETS-3404

Manual testing steps

Feature: my feature name

  Scenario: user [verb for user action]
    Given [describe expected initial app state]

    When user [verb for user action]
    Then [describe expected outcome]

Screenshots/Recordings

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After

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Performance checks (if applicable)

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  • Ideally on a mid-range device; emulator is acceptable
• I've tested with a power user scenario
  • Use these power-user SRPs to import wallets with many accounts and tokens
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---

Note

Low Risk
Display-only formatting with an opt-in override on a shared helper; no API or persistence changes.

Overview
Manage price alerts no longer collapses similar sub-dollar thresholds to the same rounded label (e.g. both showing $0.0018). The list now passes maximumFractionDigits: 15 into formatPriceWithSubscriptNotation so stored values like $0.00181069 and $0.00182069 stay distinguishable.

formatPriceWithSubscriptNotation gains an optional maximumFractionDigits override on the non-subscript path; default behavior elsewhere stays 2 decimals for ≥1 and 4 for <1. A regression test covers sub-cent threshold copy, and a small keypad doc example in create-alert was updated for extreme tiny prices.

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[metamask-ci]

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[github-actions]

🔍 Smart E2E Test Selection

• Selected E2E tags: None (no tests recommended)
• Selected Performance tags: None (no tests recommended)
• Risk Level: low
• AI Confidence: 90%

click to see 🤖 AI reasoning details

E2E Test Selection:
The PR makes targeted, low-risk changes:

1. CreatePriceAlertView.tsx: Only cosmetic changes (removed a comment, removed a blank line, updated a JSDoc example string). No functional logic changes.

2. ManagePriceAlertsView.tsx: Adds { maximumFractionDigits: 15 } to a formatPriceWithSubscriptNotation call to preserve full precision for sub-cent price alert thresholds. This is a UI display fix for a feature-flagged component.

3. format.ts (Predict utils): Extends FormatPriceWithSubscriptNotationOptions interface with an optional maximumFractionDigits property and updates formatPriceWithSubscriptNotation to use it when provided. This is a backward-compatible change — all existing callers (AssetOverview Price, TokenListItem, Bridge BatchSellTokenRow, Charts) continue to work with the same default behavior since the new parameter is optional with existing defaults.

4. ManagePriceAlertsView.test.tsx: Adds a unit test for the new precision behavior.

Why no E2E tags are needed:

• Price Alerts is a feature-flagged UI component with no existing E2E test coverage (no spec files found for PriceAlerts).
• The formatPriceWithSubscriptNotation utility change is backward-compatible — no existing callers are affected.
• The change does not touch any shared navigation, modals, confirmations, or core wallet flows.
• SmokePredictions covers Polymarket prediction markets (not price alerts).
• SmokeWalletPlatform covers token lists and asset loading, but the utility change is additive and non-breaking.
• No performance-sensitive code paths are modified.

Performance Test Selection:
The changes are limited to UI display formatting for price alert thresholds and a backward-compatible extension of a formatting utility. No performance-sensitive code paths (asset loading, rendering loops, data fetching) are modified. No performance test tags are warranted.

View GitHub Actions results

[MarioAslau]

LGTM

[gauthierpetetin]

No release label on PR. Adding release label release-8.1.0 on PR, as PR was added to branch 8.1.0 when release was cut.