feat(profile-metrics-controller): tag, canonicalize, and dedupe hardware, imported, and non-mnemonic snap accounts

[mathieuartu]

Explanation

References

Related to: https://consensyssoftware.atlassian.net/browse/MUL-2216

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 what is sent to the auth profile API and how proof-of-ownership is matched, with one-time backfill for existing opted-in users; behavior is well tested but affects metrics/auth integration.

Overview
Profile metrics sync now enriches each queued account with an optional accountSource (mnemonic, hardware, imported, or snap) derived from mnemonic entropy vs keyring type, and sends it to the auth API as account_source (unknown keyrings stay untagged).

Canonical addresses are applied when accounts are enqueued, not only when signing proofs, so hardware, imported, and non-mnemonic Snap accounts are submitted in the form the API expects. reportedAccounts persists successfully submitted canonical addresses so re-enqueue is skipped; enqueue also dedupes by canonical address to avoid double-using proof nonces.

Upgraders get a one-time accountSourceBackfillEnqueued pass (alongside existing proof backfill) that rebuilds the sync queue on first unlock. Poll behavior is tightened: empty queue skips work; non-mnemonic batches (null key) submit without proofs; proof signing matches live accounts by canonical address via refactored enqueueAccounts helpers.

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