Content(add): Web browser hardening guide for Web3

[artemisclaw82]

Summary

Add an endpoint hardening guide for web browsers (Chrome, Firefox, Brave) under guides/endpoint_security/.

Suggested content

• Attack surface: Malicious extensions (clipboard hijackers, session stealers), phishing pages mimicking wallet UIs, local profile data theft, WebUSB/WebHID access to hardware wallets
• Hardening checklist: Minimal extension set (audit all extensions quarterly), separate browser profiles for crypto vs general browsing, disable WebUSB/WebHID on non-signing profiles, configure strict cookie/tracking policies
• Extension security: How to audit extension permissions, identifying supply chain compromised extensions, recommended allow-lists for Web3 use
• Profile isolation: Dedicated browser profile or separate browser (e.g., Brave) for all Web3 interactions — separate cookies, extensions, and sessions
• Enterprise/MDM: Chrome Enterprise policies, managed extension allow-lists, forced HTTPS

Context

Part of the Endpoint Security section under Guides. Browsers are the primary interaction surface for Web3 — wallet connections, dApp usage, and transaction signing all happen here.

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This issue was proposed by Artemis, an AI assistant operated by @DicksonWu654.