fix: focused search field forces scroll

[micaelae]

Description

The bridge page's input fields are auto-focused by default, which forces the AssetPicker's search input field to keep re-focusing when it's open. As a result, the asset list keeps scrolling up to the top of the modal.

Related issues

Fixes: https://consensyssoftware.atlassian.net/browse/MMS-1856

Manual testing steps

1. Load bridge page
2. Click src token picker and verify search input component is focused
3. Scroll to bottom of asset list and wait a 5 or more seconds
4. Verify that modal does not scroll back up to search input component

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.

[metamaskbot]

Builds ready [2b6aa5d]

• builds: chrome, firefox
• builds (flask): chrome, firefox
• builds (MMI): chrome
• builds (test): chrome, firefox
• builds (test-flask): chrome, firefox
• build viz: Build System
• mv3: Bundle Size Stats
• mv2: E2e Actions Stats
• storybook: Storybook
• typescript migration: Dashboard
• all artifacts
• bundle viz:

  • background: 0, 1, 2, 3, 4, 5, 6, 7
  • common: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12
  • ui: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13
  • content-script: 0
  • offscreen: 0

Page Load Metrics (1651 ± 44 ms)

Platform	Page	Metric	Min (ms)	Max (ms)	Average (ms)	StandardDeviation (ms)	MarginOfError (ms)
Chrome	Home	firstPaint	331	1815	1594	299	144
		domContentLoaded	1463	1792	1624	83	40
		load	1478	1822	1651	91	44
		domInteractive	22	85	42	21	10
		backgroundConnect	7	133	24	28	14
		firstReactRender	16	170	70	44	21
		getState	5	65	15	18	9
		initialActions	0	1	0	0	0
		loadScripts	1094	1339	1222	65	31
		setupStore	6	71	11	14	7
		uiStartup	1678	2603	2043	263	126

Bundle size diffs

• background: 0 Bytes (0.00%)
• ui: 9 Bytes (0.00%)
• common: 0 Bytes (0.00%)