chore(3212): remove alert settings

[vinnyhoward]

Description

This PR removes the "Alerts" section from the Extension's Settings menu, preparing for future updates. The two settings previously offered here, unconnectedAccount and web3ShimUsage, are no longer configurable and will remain toggled on by default. All related UI elements and tests have been removed.

Rationale for removal:

• unconnectedAccount: This feature, which alerts users when browsing a website with an unconnected account selected, is now considered a core functionality that doesn't require user configuration.
• web3ShimUsage: This setting was introduced to inform users why a dapp might be broken due to using the deprecated window.web3 API. However, current data shows limited usage, primarily from non-crypto sites, and the
  warning only displays for connected dapps, limiting its effectiveness.

This change paves the way for repurposing the bell icon for a new Notifications feature. Testing confirms that this removal doesn't affect other parts of the extension, and all remaining tests pass successfully.

Note: Controller/state related removal will be addressed in a separate pull request and tracked in a separate issue.

Related issues

Fixes: #3212

Manual testing steps

1. Goto settings page by clicking on the more icon which are the three dots in the top right corner, and then click on settings.
2. Check to see if the "Alerts" settings are gone
3. Search for "Alerts" in the settings search and make sure nothing appears other than "Security & Privacy > Security Alerts" which is unrelated to the "Alerts" section being removed

Screenshots/Recordings

NA

Before

Menu

Search

After

Menu

Search

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]

CLA Signature Action: All authors have signed the CLA. You may need to manually re-run the blocking PR check if it doesn't pass in a few minutes.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[metamaskbot]

Builds ready [6949e85]

• 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, 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 (1872 ± 94 ms)

Platform	Page	Metric	Min (ms)	Max (ms)	Average (ms)	StandardDeviation (ms)	MarginOfError (ms)
Chrome	Home	firstPaint	1591	2274	1876	190	91
		domContentLoaded	1549	2253	1847	183	88
		load	1557	2269	1872	195	94
		domInteractive	27	80	43	17	8

Bundle size diffs [🚀 Bundle size reduced!]

• background: 0 Bytes (0.00%)
• ui: -4.86 KiB (-0.06%)
• common: -646 Bytes (-0.01%)

[dbrans]

Nice work!