Update EW introduction content

[bgravenorst]

Description

• Add a graphic that helps users quickly understand how embedded wallets differ from traditional wallets
• Updates to remove marketing tone, tighten language, and improve clarity.
• Move conceptual architecture information into a dedicated topic.
• Ensured the architecture diagram is presented as a supporting visual, not the primary source of
  information (accessibility issue).
• Added content to improve description of the architecture content.

Issue(s) fixed

Fixes #2782

Preview

https://metamask-docs-git-doc-2782-consensys-ddffed67.vercel.app/embedded-wallets/

Checklist

• If this PR updates or adds documentation content that changes or adds technical meaning, it has received an approval from an engineer or DevRel from the relevant team.
• If this PR updates or adds documentation content, it has received an approval from a technical writer.

---

Note

Low Risk
Low risk documentation-only changes; main risk is broken links/assets or unintended wording changes affecting technical meaning.

Overview
Updates the Embedded Wallets About page to remove marketing tone, tighten language, and add an onboarding comparison graphic (wallet-user-flow-comparison.svg).

Moves the conceptual architecture explanation and flow diagram into a new dedicated Architecture doc (embedded-wallets/architecture.mdx) and links to it from the About page, with a corresponding sidebar entry.

Adds list-writing guidance to the editorial voice rules (.cursor/rules/editorial-voice.mdc).

^{Reviewed by Cursor Bugbot for commit cf6562a. Bugbot is set up for automated code reviews on this repo. Configure here.}

[vercel]

The latest updates on your projects. Learn more about Vercel for GitHub.

Project	Deployment	Actions	Updated (UTC)
metamask-docs	Ready	Preview, Comment	Apr 8, 2026 11:13pm

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

^{Bugbot Autofix is OFF. To automatically fix reported issues with cloud agents, have a team admin enable autofix in the Cursor dashboard.}

[yashovardhan]

LGTM