Add web and email to known service protocols

[a6b8]

Problem

The RegistrationValidator only recognizes 5 service protocols:

const KNOWN_PROTOCOLS = [ 'mcp', 'a2a', 'oasf', 'ens', 'did' ]

The ERC-8004 spec defines 7 protocols, including web and email:

{ "name": "web", "endpoint": "https://web.agentxyz.com/" },
{ "name": "email", "endpoint": "mail@myagent.com" }

Impact

• Agents with web or email services get false REG-026 warnings: Unknown protocol "web" (known: mcp, a2a, oasf, ens, did)
• web is likely one of the most commonly used service types

Required Changes

In RegistrationValidator.mjs:

// Current
const KNOWN_PROTOCOLS = [ 'mcp', 'a2a', 'oasf', 'ens', 'did' ]

// Should be
const KNOWN_PROTOCOLS = [ 'web', 'a2a', 'mcp', 'oasf', 'ens', 'did', 'email' ]

Order matches spec example sequence.

Validation Data

Part of REG-026 count (~408 on Ethereum alone) are web and email services being falsely flagged.