fix: Token details should not display zero balance for tokens without marketData

[gambinish]

Description

On main asset list, if a token doesn't have marketData, we do not display the fiat value. On tokenDetails we were falling back to zero balance (this is incorrect)

This PR adds a fix to not fallback to zero balance, and to instead simply omit the value.

Related issues

Fixes: #29244

Manual testing steps

1. Add a memcoin without marketData
2. Validate that no fiat value is shown on main asset list
3. Validate that no fiat value is shown on token details (should not display zero value)
4. Ensure nothing results in NaN value.

Screenshots/Recordings

Before

After

Pre-merge author checklist

• I've followed MetaMask Contributor Docs and MetaMask Extension Coding Standards.
• I've completed the PR template to the best of my ability
• I’ve included tests if applicable
• I’ve documented my code using JSDoc format if applicable
• I’ve applied the right labels on the PR (see labeling guidelines). Not required for external contributors.

Pre-merge reviewer checklist

• I've manually tested the PR (e.g. pull and build branch, run the app, test code being changed).
• I confirm that this PR addresses all acceptance criteria described in the ticket it closes and includes the necessary testing evidence such as recordings and or screenshots.

[github-actions]

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[sentry-io]

🔍 Existing Issues For Review

Your pull request is modifying functions with the following pre-existing issues:

📄 File: ui/components/app/wallet-overview/coin-buttons.tsx

Function	Unhandled Issue
setCorrectChain	Error: Had a problem changing networks! /popup.html Event Count: 3 Affected Users: 0

---

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[metamaskbot]

Builds ready [d9c2791]

• builds: chrome, firefox
• builds (beta): chrome
• builds (flask): chrome, firefox
• builds (MMI): chrome, firefox
• builds (test): chrome, firefox
• builds (test-flask): chrome, firefox
• build viz: Build System
• mv3: Background Module Init Stats
• mv3: UI Init Stats
• mv3: Module Load Stats
• mv3: Bundle Size Stats
• mv2: E2e Actions Stats
• code coverage: Report
• storybook: Storybook
• typescript migration: Dashboard
• all artifacts
• bundle viz:

  • background: 0, 1, 2, 3, 4, 5, 6
  • common: 0, 1, 10, 11, 12, 2, 3, 4, 5, 6, 7, 8, 9
  • content-script: 0
  • offscreen: 0
  • ui: 0, 1, 10, 11, 12, 2, 3, 4, 5, 6, 7, 8, 9

Page Load Metrics (1825 ± 89 ms)

Platform	Page	Metric	Min (ms)	Max (ms)	Average (ms)	StandardDeviation (ms)	MarginOfError (ms)
Chrome	Home	firstPaint	1571	2381	1822	186	89
		domContentLoaded	1562	2368	1798	186	89
		load	1571	2384	1825	184	89
		domInteractive	20	194	49	44	21
		backgroundConnect	10	77	26	18	8
		firstReactRender	17	82	53	23	11
		getState	5	61	17	18	9
		initialActions	0	1	0	0	0
		loadScripts	1163	1938	1368	187	90
		setupStore	6	86	14	19	9
		uiStartup	1794	2794	2088	245	117

Bundle size diffs

• background: 0 Bytes (0.00%)
• ui: -71 Bytes (-0.00%)
• common: 0 Bytes (0.00%)

[bergeron]

I was trying to follow testing steps, but for some reason I'm seeing $0.00 on the main token list 🤔

nevermind, the repro is a token without market data, not a token without balance. Have to pick some obscure token that we don't have prices for.

Update: LGTM, tested before and after

[metamaskbot]

Builds ready [b2a79e5]

• builds: chrome, firefox
• builds (beta): chrome
• builds (flask): chrome, firefox
• builds (MMI): chrome, firefox
• builds (test): chrome, firefox
• builds (test-flask): chrome, firefox
• build viz: Build System
• mv3: Background Module Init Stats
• mv3: UI Init Stats
• mv3: Module Load Stats
• mv3: Bundle Size Stats
• mv2: E2e Actions Stats
• code coverage: Report
• storybook: Storybook
• typescript migration: Dashboard
• all artifacts
• bundle viz:

  • background: 0, 1, 2, 3, 4, 5, 6
  • common: 0, 1, 10, 11, 12, 2, 3, 4, 5, 6, 7, 8, 9
  • content-script: 0
  • offscreen: 0
  • ui: 0, 1, 10, 11, 12, 2, 3, 4, 5, 6, 7, 8, 9

Page Load Metrics (1800 ± 75 ms)

Platform	Page	Metric	Min (ms)	Max (ms)	Average (ms)	StandardDeviation (ms)	MarginOfError (ms)
Chrome	Home	firstPaint	1599	2271	1802	164	79
		domContentLoaded	1579	2199	1774	157	75
		load	1599	2216	1800	157	75
		domInteractive	26	89	44	19	9
		backgroundConnect	12	69	28	20	9
		firstReactRender	17	97	38	25	12
		getState	6	58	21	19	9
		initialActions	0	1	0	0	0
		loadScripts	1118	1653	1324	133	64
		setupStore	7	68	18	19	9
		uiStartup	1798	2682	2071	234	112

Bundle size diffs

• background: 0 Bytes (0.00%)
• ui: 12 Bytes (0.00%)
• common: 0 Bytes (0.00%)