feat(profile-sync-controller): add SRP tagging

[mathieuartu]

Explanation

References

Related to: https://consensyssoftware.atlassian.net/browse/MUL-2063

Checklist

• I've updated the test suite for new or updated code as appropriate
• I've updated documentation (JSDoc, Markdown, etc.) for new or updated code as appropriate
• I've communicated my changes to consumers by updating changelogs for packages I've changed
• I've introduced breaking changes in this PR and have prepared draft pull requests for clients and consumer packages to resolve them

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Note

Medium Risk
Changes the SRP login signed message format and auth request payload; misalignment with the auth server or wrong identifier_type mapping could affect sign-in or analytics, though seedless lookup failures degrade to SRP.

Overview
Extends SRP profile login so /srp/login carries richer metadata: the signed raw_message becomes metamask:<nonce>:<pubkey>:primary|secondary (first HD entropy source vs any other), and the request body includes metametrics.identifier_type (SRP, GOOGLE, APPLE, or TELEGRAM).

AuthenticationController resolves the tag from the entropy source and maps the primary source’s social vault via SeedlessOnboardingController:getState (authConnection); secondary SRPs stay SRP, and missing/unavailable seedless state soft-fails to SRP. The SRP JWT bearer flow and authenticate() service accept optional getLoginTag / getLoginIdentifierType hooks (defaults: primary and SRP). Multi-SRP sign-in now signs two distinct messages instead of one.

Adds @metamask/seedless-onboarding-controller as a dependency and documents the change in the package changelog.

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