[Bug]: Simulation fiat tooltip should show full maxPrecision value, no ellipsis, and not overflow

**Describe the bug**

Hovering on fiat value displays the same text when ellipsis is shown in the tooltip.

We should also handle overflow if it still exists

**Expected behavior**

Hovering on fiat value should display full maxPrecision value and no ellipsis in the tooltip.

**Steps to reproduce**

1. Set ENABLE_CONFIRMATION_REDESIGN=true to true in .metamaskrc
2. Enable confirmation_redesign in Launch Darkly
3. Turn on Improved Signatures setting
4. Turn on Simulation setting
5. Open a Permit w/ a large number a. Example: https://develop.d3bkcslj57l47p.amplifyapp.com/ → "Permit 2 - Single" button
6. Observe value in simulation

**Error messages or log output**

```shell

```

**Detection stage**

In production (default)

**Version**

12.9.2

**Build type**

None

**Browser**

Chrome

**Operating system**

MacOS

Reproduce the issue by following the listed .metamaskrc, LaunchDarkly, Improved Signatures, and Simulation steps, then open the Permit 2 - Single example. Locate the simulation fiat value tooltip and verify the displayed value uses full maxPrecision without ellipsis or overflow; done means both tooltip requirements hold for the large-number case.

Written by the indexing model from the issue text.