fix(utils): prevent scientific notation in formatTokenAmount for large decimals

[jaffarkeikei]

What changed? Why?

formatTokenAmount now returns proper decimal notation instead of scientific notation for small amounts with large decimals.

Notes to reviewers

Without fix:

formatTokenAmount('1000', 50)  // Returns "1e-47" ❌

With fix:

formatTokenAmount('1000', 50)  // Returns "0.00000...001" ✓

Uses toFixed() for small numbers (<1) to avoid scientific notation, then strips trailing zeros.

How has it been tested?

Manual testing:

• Large decimals (50): proper decimal notation
• Normal decimals (18): works as before
• Zero/negative amounts: handled correctly

[vercel]

@jaffarkeikei is attempting to deploy a commit to the Coinbase Team on Vercel.

A member of the Team first needs to authorize it.

[cb-heimdall]

🟡 Heimdall Review Status

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